Answer: do not be an entrepreneur!
It's impossible to be a successful entrepreneur and to be realistic, we will never succeed if we see the reality of things.
The reality is that it takes time, patience and accepting to be told NO ... all the time!
If we succeed, it is because we believe in it and we always see the good side of things, we accept the no. Seeing the good side of things is not wearing pink glasses and believing in unicorns. It is to see a big pile of manure and to say that it is part of the course and that it must be shoveled to cross it.
My "farmer" side that has just come out »;)