We have a monthly subscription and an annual subscription with a 3-day free trial.
The monthly converts fine. On the annual, trials tend to enter billing retry rather than convert — users don't cancel, the charge just fails.
We've audited our implementation and found nothing on our side that participates in the renewal charge.
What can a developer actually do about this? Does trial length, price point, or using a paid introductory offer instead of a free trial make a difference?