I'll go first.
E-commerce + finding winning products 😅
Why?
Convoluted thinking that produced the wrong mindset + impatience.
"If I find what I think is good (because I know what people are thinking, all day every day), then I can make bank, then I can live a dream, then life will be good."
I could spot a trend, but results and betting on being "right" about what people wanted and needed were way off.
Anyway, if I were to do it all again with the knowledge I had today, it'd be to throw as many tests and not to get too attached to the results.
Do you have an experience like this?