There are connection between things, but not so often

I used to have a false believe that when I'm doing things successfully, I'll be successful continuously, and when I'm doing things wrong, the unlucky will persist.

Both assumptions have their sound part, but there are reasons behind them. The reason is Familiarity.

When I kept doing one thing in one area, the familiarity grows greater and greater, which greatly reduces the chances of making mistakes. But when I tried to enter another area, the rules and logic quickly become unfamiliar, and I began blundering.

The worst thing is not blundering itself, but the false believe that I was still doing things in the right way! So, I must keep cautious on such circumstances.