# The Cold-Start Problem: Getting the Engine to Turn Over

Phase 6.6 finds the growth loop. But a loop is an engine, and an engine has to turn over the *first* time. Some products are useful to the very first user on their own (a habit tracker works with one person). Others are worthless until a crowd is already there: a marketplace with no sellers, a social app where none of your friends are, a directory with three entries. That's the **cold-start problem**, and it's the single most common way these die: the first person lands, finds an empty room, and never comes back.

Pull this in when the Phase 6.6 question, *"does your app give the very first user something on their own, or is it only useful once lots of people are already on it?"*, lands on the second answer.

The good news: this is a solved problem. Pick a strategy that fits, build for it, and you sidestep the empty room.

## The seven strategies

You usually combine two or three of these, not just one.

**1. Single-player mode first ("come for the tool, stay for the network").** Make it genuinely useful to ONE person, alone, before the network exists. They come for the standalone tool; the network switches on later once enough of them are in. Instagram was a photo-filter app before it was a social network. OpenTable was reservation software for restaurants before it was a place diners browse. Vinti (my own) is a virtual dressing room and AI stylist that's useful solo, and only opens clothes-swapping once enough wardrobes are loaded. This is the strongest opener for a beginner, because you can launch and get value to real users on day one, with no crowd required.

**2. Start absurdly narrow (one atomic network).** Don't launch "everywhere." Launch in the smallest pocket that's already dense enough to feel alive: one city, one campus, one subreddit, one apartment building. Facebook started at one university. Tinder seeded itself at single college parties. Uber launched in one neighborhood of one city. A small full room beats a huge empty one. Win it, then copy the playbook to the next pocket.

**3. Hold the network behind a threshold.** Don't expose the directory, the feed, or the map until you've crossed a minimum, so the first visitor never lands on an empty page. ClearList won't open its city listings until about 50 sale pages exist in that city, because otherwise someone arrives at a near-empty page for a city they don't even live in, decides the whole thing is dead, and never returns. Until you hit the threshold, you keep the network hidden and run single-player mode (strategy 1) or seed by hand (strategy 5).

**4. Seed the hard side by hand.** One side is always harder to get than the other, usually the supply (the sellers, the hosts, the creators), because making something takes more effort than consuming it. Go get them one at a time, personally. This is "do things that don't scale": Airbnb's founders went door to door and photographed early listings themselves. It feels slow and unglamorous. It's also how almost every marketplace actually started.

**5. Pick which side to build first, and why.** You can't usually grow both sides at once, so choose. The rule of thumb: seed the **hard side** first (from strategy 4), because once you have supply, demand is easier to pull in, an empty store repels shoppers, but a stocked store with no shoppers can still go find them. Decide your first side on purpose and aim your whole early effort there.

**6. Seed supply honestly, never fake demand.** It is completely fine to fill the app with your *own* real inventory or content at the start, real listings, real articles, a real first batch you made yourself, so the first visitor doesn't see an empty room. What you must never do is fake **demand**: fake "3 people watching this," fake reviews, fake "online now" dots, fake scarcity. That's a dark pattern (the ethical lens from Phase 2 applies right here), it betrays the exact trust a young marketplace can't afford to lose, and people can smell it. Seed the shelves with real goods; never fake the crowd.

**7. Set, and watch, your minimum liquidity.** "Liquidity" just means: enough of both sides that someone who shows up actually finds what they came for, a buyer finds something to buy, a seller finds someone to sell to. Name the number that means "it's safe to open the doors here", ClearList's is "50 sale pages in this city." Below it, you stay in single-player or by-hand mode. Above it, you let the network show. It's the one metric a cold-start product lives by.

## How to choose

- **Can the app be useful to one person alone, even in a stripped-down way?** Then lead with **single-player mode** (1). It's the safest, because you ship value from day one and grow the network underneath.
- **Is it inherently group-only (a swap, a chat, a match)?** Then combine **start narrow** (2) + **seed the hard side by hand** (4) + **a threshold** (3), and keep the network hidden until you cross it.
- **Either way:** decide your **hard side / first side** (5), seed it with **real supply, never fake demand** (6), and pick the **liquidity number** (7) that tells you it's working.

Write the chosen strategy and the threshold straight into the plan's Growth Loop section. A marketplace plan that doesn't name how it survives its first month is a plan with a hole in exactly the place these products fail.
