Given there is absolutely no substitute for simply running a test to know whether it’s going to be successful, the very best growth teams optimize for velocity of A/B tests they can run.
There are a lot of things that slow down testing velocity – all of which can be optimized. Ability to divide up your audience into orthogonal sub-segments is important to ensure your tests don’t interfere but you can run as many as possible simultaneously. Improving the throughput of test analysis is important so you limit the time you can decide whether to ramp a test or move on to the next variant. Developing a backlog of upcoming tests and regularly grooming that backlog will help you ensure you always are prepared for the next test. Streamlining your test ideation and brainstorming process will also improve the speed of getting good variants to run.
The point is the single most important thing a growth team can do is not picking the right variant to test, but simply increasing the velocity of tests you are running.
(1) Cf. Instilling a culture of experimentation from day one.
(2) Cf. Three advantages of experimenting a lot.