The goal for the first ninety days is roughly thirty accounts writing content every week. Not signups, not revenue, not a fundraising signal.
The alternatives were all more flattering and all worse. Signup volume is the easiest number to move and the least informative — it measures how loudly you talked, and a product with a broken second week produces exactly the same signup chart as a product with a great one. Revenue is premature when the product is deliberately close to free. A fundraising signal is a number chosen to impress someone, which is a different activity from learning whether the thing works.
What decided it: thirty is small enough to be achievable without a launch, and depth is the only thing nobody has proven. Every other goal we could pick already assumes the answer to the question we most need to ask, which is whether anyone comes back. A number that small is also honest in a useful way — it can be reached by hand, one user at a time, which means failing to reach it is unambiguous information rather than a marketing problem.
The cost of this choice, stated plainly: it will look unimpressive to anyone who asks how launch went.