Candidates often say, “I worked at [bigger similar company], and we can run the same playbook. You just haven’t thought deeply enough about it.”

It makes sense on the surface, but it’s a dangerous pitch.

Why?

It turns out companies grow differently, even in the same industry. The strengths of the product, the founding team, and the timing all affect how companies grow.

For example, we’ve worked with multiple coding bootcamps. One grew through PR and paid social media ads; another grew through content and cold outreach; another grew through Twitter. There was no “one way” they grew.

The problem with these hires isn’t actually the initial playbook. It’s that they’re too specialized.

This means they can’t adapt when things go wrong.

Someone who worked in email marketing their whole career won’t try business development or custom sponsorship. They overlook referral programs. They don’t run digital ads.

When plans go awry, you need your head of growth to hack together quick, practical experiments that validate whether a strategy has the potential to work. Then, once you have proof, hire a specialist.

If you hire the specialist too early, they’ll slow down your company while they spin their wheels.

They end up outsourcing the work…or never do it at all. As a result, experiments take forever to launch — and you never get users.

A client of ours made this hire. He spent days poring over data, brainstorming ideas in his own bubble, and calling out problems with the funnel. But, after all that work, he pitched bland experiments that didn’t build on his research.

Worse, he took forever to launch his experiments. For example, he spent two weeks redoing a drip sequence that was a few emails long — something that should take a few days at most.

It got to the point where the founder told him, “Email five users to ask for an interview this week. That’s all you have to do. Just email them by the end of the week.”

No emails went out.

The hire was a fiasco. Luckily, our client knew what a good growth process looked like. Within two months, they fired him after giving him multiple chances to prove his worth.

Another startup hired someone who spent weeks on a “product marketing manifesto” but never launched a single experiment.

These hires weren't stupid.

They were just used to managing larger teams at companies that move slowly. If you’re an early-stage startup, you don’t have that time.

There’s a strong incentive for growth hires to show numbers going up. It feels like momentum and motivates the team.

The problem? Mid-funnel wins have a nasty habit of not translating into real users. These metrics are also much easier to game.

We once sat in on growth meetings for a B2B client and heard two very different stories. The growth person was constantly gushing about how “LinkedIn ads were working,” “cost per lead was dropping,” and “lead volume was going up.” At the same time, the founder was confused because no deals were actually closing.

This startup had spent tens of thousands on ads — for months — with no revenue to show for it.

When we dug in, we learned that the so-called “leads” were extremely low-intent. Some wanted jobs at the company, some expected a training program instead of a product, and some were personal emails from countries the startup never wanted to target.

According to the growth person, these leads just “needed nurturing” and were “early in the buying journey.”

But the growth person had never looked at the individual leads. If they had, they would have realized the problems within minutes. Instead, they just looked at the high-level reports and saw the cost per lead dropping.

Why?

For one, it took work. They would have to manually click through each report and sales interaction in HubSpot to learn about these leads. But they could report on lead volume and cost per lead in seconds.

For another, they were territorial and defensive. Even when the founder explicitly asked them to pull reports using revenue instead of leads, they refused. They prioritized their ego and optics over what was useful for the team, and they shot themselves in the foot.

It still took a year for the startup to fire them.

(By the way, their argument of “our leads need nurturing” is sometimes OK at larger companies if it’s grounded in proper research. Not at early startups. Those leads are seldom worth the effort.)

We see this most with contractors you find through a marketplace like Upwork, Toptal, etc.

These people can be technically skilled but have a hard time finding real wins. They’ll talk your ear off about the intricacies of onboarding flows or Google Ads, but they won’t tailor the tools to your user.

Their writing tends to be vanilla and weak. Because they don’t really care about your user, their tone sounds like a term paper or bureaucratic announcement.

They don’t like talking with users. When they do, they ask rote questions and miss the nuance in answers.

They rarely mix with the rest of the company, so they don’t cross-pollinate learnings and ideas. Instead, they come up with dull, predictable experiments on their own.

The main consequence? Their ideas don’t work.

Thankfully, this trait is easier to spot. They don’t ask many questions when you interview them, they overindex on your competition, and they’re more excited by your large market size than your customer or mission.

Here’s what confuses founders: other hires can have mercenary qualities. A classic example is a Google engineer; even though Google’s business depends on ad revenue, most of their engineers don’t care about serving ads to marketers. They just like solving massive problems with smart people using cool math and sophisticated programming.

This mindset works when you’re building a product. It doesn’t when you’re selling it.

Growth marketers write a lot of copy. If you can't write clearly, users won't understand you, and your copy will convert worse. This means your company will lose money.

You also have to justify your thinking to the team in Slack messages, emails, slide decks, etc. People who can't follow your reasoning are less likely to buy into your ideas.

As a growth marketer, you’ll be looking at a lot of funnel data and running tests. You’ll estimate conversion rates, ballpark how much a user will cost from early data, and determine if a test has enough data to be valid.

This means you’ll have to be good at basic mental math, multiplication, weighted averages, and fractions/percentages.

You don’t need an advanced degree in statistics to do this. There are shortcuts, but you do need a basic facility with numbers and Excel/Google Sheets.

You probably already look for this. No one ever got rejected for learning too quickly.

If initial experiments don’t work, a curious hire isn’t likely to quit. They’re just learning what to avoid in the future; it’s part of their career growth.

Curious employees can outshine incurious ones within months.

Their answer should touch on a down-funnel success metric, such as active users, revenue, or CAC.

If they talk about mid-funnel metrics (like traffic, leads, CPAs), they need to also talk about “intent”; whether these people are actively looking to buy. It’s not enough for a lead to be the right demographic or job title.

They should understand the tradeoff between speed and quality of metrics: up-funnel metrics show results faster, but they don’t always translate into customers.

Scaling matters, too: how many users can you get before a channel taps out? Does the channel naturally compound? They should be thinking about all these things.

You’ll have to ask follow-up questions to meaningfully get a sense of how scrappy they are:

Suppose they’re doing keyword research for SEO or PPC ads. They should be able to crack open the keyword planner and Ahrefs or SEMRush. It’s a smell if they’ve never used these tools before.

If they mention bringing on an agency or hire, redirect them and say, “Pretend we don’t have the money to do that — what would you do instead?”

Drill into specifics and be ruthless. Find the edges of their knowledge. Ask them to explain things you don’t know.

If their answers confuse you more than teach you, it’s a sign they’ll waste your time.

Their first couple weeks should be about understanding users (”market research”) and setting up basic data reporting.

It’s a red flag if they don’t mention user interviews and nitty-gritty qualitative research (reading support tickets, listening to sales calls, etc.). It’s a green flag if they talk about setting up an ongoing way to learn from users.

Ask them how they’d make a report. Ask what they’d do if engineers were busy and couldn’t pull certain data. This feels out whether they’ll do grunt work like copying-and-pasting into spreadsheets.

The first couple of months are for running experiments themselves. If they talk about bringing on agencies or new hires, watch out. Brand redesigns are red flags. A full site overhaul is a red flag. Sending manual emails is a green flag.

Beyond that, they shouldn’t be too prescriptive about what the first year looks like.

Good answers sound like decision trees: “If conference booths work, we look into bringing on a business development team. If it doesn’t, we look into sponsoring podcasts or launching the newsletter we talked about.”

Firstly, their answer should always involve some calculation of CAC: the cost of actually acquiring a customer.

It’s also good if they talk about timing (for example, is there a lag between when you spend on ads and when a customer actually pays?). You may need debt to cover the cash gap.

The rest of their answer depends on the channel. Here are some common ones:

Inexperienced marketers immediately jump to conclusions. Experienced ones methodically debug the funnel: “Where did the dropoff happen in the funnel? Was it at the checkout stage? Between the landing page and product page?”

Once they know where to focus, they tease out segments of the data: “Was there a difference between mobile and desktop users? Did we get an influx of users from a new country? What was our channel mix?” Et cetera.

Their answer should be both qualitative and quantitative.

Qualitatively, they should be digging into your product’s value props: does one persona have a much worse alternative? Is one persona stickier? They should mention that painkillers are typically easier to grow than vitamins — a signal for where to focus.

Quantitatively, they should do a few things:

1) Rough market sizing: how many dentists vs. piano technicians are there in the US? Some mental math is required here.

2) Ask about CAC between the two markets.

3) Ask for retention numbers. (The quantitative version of “is one persona stickier?”)

If our guide has done its job, you’ll hear some of the things we mention. Beyond that, make sure they teach you something in a way you can understand. They’ll have to do the same with users (and their potential future team).

There are generally two phases: before you crack a strategy and after you crack it.

Before you crack a strategy, they should be 80/20ing a bunch of the experiments themselves.

Once you crack a strategy, you hire a team of specialists to execute and scale it.

Their answer should be similar to the “walk me through, step-by-step, how you’d test [a particular channel]” question, but more strategic.

First, they should be asking you a lot of questions about your users and strengths as a company before they jump to an answer. It’s a plus if they come up with a compounding strategy that involves growth loops.

Then, you should ask them the same followup questions to figure out how scrappy they are.