Played Bloom, two runs, about a minute in total.
The second I stopped caring: about ten seconds into the first run. The cloud turned grey and stopped raining, and I didn't know why. There was a hint under the plant, but it was small and faint and I only read it later. I pulled the cloud away, the plant wilted back, and then "it dried out · tap to try again". The page says there's no fail state, so it felt like the game broke a promise rather than me losing.
Second run, knowing the rule, it clicked: rain until the cloud runs dry, pull it away to refill, bring it back. The bud glowing just before it opens is the best moment in it. The flower opened at around 35 seconds. Then I let go, and it started closing within a few seconds, with nothing to mark that I'd got there. That was the second dip.
One thing I'd try: show the refill rule through the cloud instead of text (it drifts off on its own when it's empty, say), and when the flower opens, hold it open for a beat and count it, so letting go afterwards doesn't undo it. And if "no fail state" is meant to stay true, the dried-out screen is the thing to cut.
Our build has moved a long way since your first pass (one-click start, letter after the first catch, and a lot more). If you want to take the second pass you offered, the latest notes are here: https://dlgkrwn02.itch.io/deulsup-dogam/devlog/1680078/bigger-catches-margin-notes-cabin-guide-10551062-