Getting wedded to an idea and sticking with it too long. Don't marry a single idea. Remember, ideas are the currency of entrepreneurs. Play with many ideas and see which ones bring money and success. Trying to be something other than an entreprenur.
Entrepreneurs are entrepreneurs.
You'll give yourself a hernia if you try to act like other people. Your difference is your strength. Believing your own b.s. Entrepreneurs are genetically wired to be optimistic. Ignoring your cash position.