The worst for me would be is postponing for trading. It's only good if you only bought and hold btc but I highly doubt it for most of the traders. So postponing is like being an irresponsible trading because things can happen fast in crypto and just taking an off for months can give you a lot of surprising changes that will definitely tell to yourself that you messed up. Panic selling will only happen on you first trades because you will learn valuable things as you move forward.