Maybe regret is too strong of a word to use. Let's face it, we're all human beings at the end of the day. At some point we all make some mistakes in our careers. But not all mistakes are all bad, in fact it's a great learning opportunity because we knew what went wrong.
For me, I learnt that when the task you're handling is going south, it's better to share the news as early as possible and ask teammates for help instead of wrecking my head trying to figure it out on my own. There's no shame in asking for help. 😀
If you had a chance to go back "re-do" it, how would you have done it better/ to avoid it?