What is the best and worst investment you have made?

Best investment - in myself via investment courses, especially for the one on options portfolio management. Allowing me to double my account size last year and am targeting 60% this year.

Worst investment - couple of them come to mind. Went into the ipo for XMH when I didn't know better. Now the stock is languishing. Another one would be to invest into Asian Pay Television Trust for the high yield. Stock tanked when dividend was cut so am sitting on some paper losses now

The worst investment i made was because of my lack of knowledge and invested on a company without enough research. Luckily i only lost the commission as the price didnt change much.