People approach any task with one of two mindsets: what I call the "Be-Good" mindset, where your focus is on proving that you have a lot of ability and already know what you're doing, and the "Get-Better" mindset, where your focus is on developing ability. You can think of it as the difference between wanting to prove that you are smart, and wanting to get smarter.
The problem with the Be-Good mindset is that it tends to cause problems when we are faced with something unfamiliar or difficult. We start worrying about making mistakes, because mistakes mean that we lack ability, and this creates a lot of anxiety and frustration.
Anxiety and frustration, in turn, undermine performance by compromising our working memory, disrupting the many cognitive processes we rely on for creative and analytical thinking.
Also, when we focus too much on doing things perfectly (i.e., being good), we don't engage in the kind of exploratory thinking and behavior that creates new knowledge and innovation.
The "Be-Good" and "Get-Better" mindsets are identical to Carol Dweck's Fixed and Growth mindsets. The "Get Better" mindset is much more useful when approaching new tasks. One thing I, as a recovering "Be-Gooder," have started to come to grips with is this: I notice my mistakes and feel them more acutely than anyone else.
So if you're trying new things, forgive yourself when you make mistakes. Colleagues will forget them, especially if you put the learnings to use immediately. Soon, they will only see your expertise. The missteps that built that expertise will fade away.
Disclosure: 99u.com occasionally publishes things I write.