Ask HN: What are your sidehustle pitfalls?

to all of you on HN that have attempted or considered a sidehustle, be it saas or selling sandwiches, what has been the most challenging or counter intuitive pitfall along the way across:

1) actually getting started, what held you back from doing a sidehustle?

2) how did you keep at it when things got hard?

3) scaling it or not?

from all the sidehustle marketing posts on hn it seems there's a formula i'm missing, as i've never been able to get something set up. insights from the battle hardened side hustlers would share the stoke!