Tons more lucky than most. My last startup job misclassified me when funds got tight. A friend of mine who joined later never got paid (good luck filing a wage claim in WA state if L&I’s system still thinks you’re a contractor).
The big one for me was realizing that my boss had lied about knowing how to code. Other red flags include code and documentation quality, how the business sells itself to potential customers (does it greatly oversell it’s abilities), the expiration date of the coffee/tea in the break room (I got food poisoning when I drank the startup’s three year expired tea - the founders were still wondering why they felt like crap all the time when I left), etc.
It’s really a bunch of little things that, when seen as off all at once, will trip your spidey sense to jump ship.
The rest basically failures or zombies that made me no extra money.
Probably a little more lucky than most.