Forty signups a month and every A/B test comes back significant, I do not believe any of them
Small product, about forty signups a month. I have been running tests on the landing page because that is what you are supposed to do.
The last one said a headline change improved conversion by sixty percent, based on eleven conversions against seven. The tool reported it as significant and suggested I ship it.
I shipped it, and the following month looked exactly like the months before.
I now do not trust any of the results, but I also do not know what to do instead. Waiting until I have thousands of visitors means doing nothing for a year. What do people at this size actually do to decide what to change?
@no_power_at_forty · 3w ago
Your instinct is right and the arithmetic backs it up: at eleven versus seven you cannot detect anything, and the tool telling you otherwise is the tool being used outside its range.
The short version of why. To detect a difference you need enough events that ordinary randomness cannot produce the gap you are seeing. With single-digit conversion counts, randomness produces gaps like yours constantly - flip a coin eighteen times and you will regularly get eleven and seven, and nobody would call that a biased coin.
Two specific traps you have probably also hit:
Peeking. If you check the result as it accumulates and stop when it looks significant, you will find significance almost every time, in noise, guaranteed. Sequential looking at a running test breaks the statistics completely, and every dashboard invites it.
Small effects need enormous samples. People imagine a test detects a ten percent improvement. Detecting that reliably needs sample sizes in the thousands per variant. At forty signups a month you would be waiting years, not a year.
So the honest position: at your size, A/B testing is not a tool you own yet. That is not a failure, it is a scale fact. The good news is that the alternatives are better at this size anyway, and both of the answers below are things you can do this week.
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