Not putting stuff out thinking what people will think.
Creating work and deleting it because you were embarrassed by it.
Wasting time on stuff that offers low ROI.
Procrastinating, more thinking, less doing.
Not showcasing your work.
Working for free for too long.
Not discussing money early in a client conversation.
Not keeping a regular schedule to create, thinking a few all-nighters will substitute lack of creation on all other days.
Waiting for the right time, and wasting time and opportunities.
Not charging (enough) money early in their career, because if enough people pay for what you make, means you are on the right track.
Trying too many things too soon, without giving yourself a chance to get good at one thing and allowing yourself to be seen as an expert.
Working without a guide or mentor.
Not respecting deadlines, own or clients.
Telling yourself that you need to wait to launch until you got better.
Thinking that tools or lack of them will make or break you.
Getting fancy, and creating without thinking about what others want.
Or getting too outwardly focussed and doing what does not make you happy.
Getting the superwoman syndrome and trying to do everything yourself and not asking for help when you should.
Not trying anything new, worrying about messing up.
Working so much that there is no time for self-care and burn yourself out.
Equating working endlessly with growth.