Growth: the wedge channel before the rest.

Product-led growth (PLG) means the product itself is the salesperson — the install is friction-free, the value shows up before any onboarding call, and the free tier is the first frame of the funnel. Community-led growth means users find you through a peer they already trust — a creator, a subreddit moderator, a friend in a Discord — long before they trust you. Each works alone in narrow cases; together they compound, because PLG converts what community-led delivers.

The deciding question is whether your "magic moment" is visible. If a stranger can watch your product work on someone else's screen and immediately understand the value, community-led is on the table. If understanding the value requires a 20-minute setup, only sales-led survives. Hybrids fail not because both halves are weak, but because founders forget that PLG without a community fuse means no first hundred, and community-led without a polished free product means churn before retention math kicks in.

The Crossing-the-Chasm test for a beachhead is four-part: (1) the niche must be small enough that you can dominate it, (2) the pain must be acute enough to tolerate v1 bugs, (3) the niche must talk to itself so word-of-mouth has a substrate, and (4) winning here must teach the rest of the market what you do. A beachhead is not your best customer. It is your most educational customer.

Founders fail by listing five "early adopter segments" and treating them as equally weighted. They aren't. Picking one means saying out loud which three you are deferring — and writing them down so the team stops drifting back to them every standup. The beachhead is the only segment that gets your homepage copy, your demo script, and your founder time for the first ninety days.

Rank channels by three numbers: cost per acquisition, founder-effort per signup, and monthly volume ceiling. The right channel for week 1 is rarely the largest — it is the one where your effort produces a measurable signal fastest. A channel with a 4-month lag (SEO) is correct to invest in early only as a side bet, because it cannot tell you whether you are right or wrong before your runway burns. Channels that produce signal in days, not months, deserve the founder's calendar.

Two anti-patterns dominate. First, "try everything" — running five channels at quarter-effort, learning nothing from any of them. Second, "scale before signal" — pouring money into the first channel that returned a positive number, before testing whether that number was repeatable. The discipline is: at most three channels in week 1, each with a numeric weekly target, and a written kill-line under each.

Three loops matter for consumer software. Product loops — every user action creates a signal another stranger sees (Loom's watermark, Calendly's branded booking page, Dropbox's shared folder). Content loops — every user generates an artifact that pulls new users in (a creator's demo video, a transcript, a screenshot). Data loops — every session improves the product for the next session (better translation, better voice routing, better personalisation). The first two grow the top of the funnel; the third grows the floor — the lowest retention number you'll ever see.

Retention is the only metric that turns growth from a treadmill into a flywheel. D7 below 30% means you are running an acquisition business; D7 above 40% means you are running a product. Most consumer-AI tools die in the gap between activation and D7 because activation feels like victory and D7 feels like work.