Maybe for sharing and learning here.

My mistake was not learning to save up earlier in my career.  back then was a jolly CC user , have expensive hobbies and always travel for fun to and from (i'm guessing u call YOLO these days). Dunno all my money went even though worked a long time.

I wish I realized and be more financially aware sooner than later.

Second mistake is buying a car and house that is not affordable  .

I wish back then I used a cheaper car, as depreciation kills the value and fast forward 10 years all sort of problems came out .

Although the house I bought is in a decent location, I felt that it was overpriced. Back then it was all the rage for "Property investment". If I had the chance, I would undo this mistake by not buying a house at all, and instead just park the savings in gold and use it to buy house for own self stay .

What did you do that you regretted? Past cannot change anymore, perhaps we could state this as a reminder for ourselves.