The first difficulty is structural – what is needed for the task?
The tools required, the design ability, understanding the manufacturing or publication process, or the group of movements that might help you progress in a particular set of skills.
The second difficulty is far greater, it is emotional – the ability and willingness to communicate effectively with others involved, the acceptance of where you are, the ability to keep going despite not being where you want to be (still!), the decision to finally start after you have talked about your idea for a year, or the ability to ask for help.
When we look at the obstacles that we will face in any given process, the we tend to jump towards the structural.
They are sexy, they seem to be in line with the process. However, in the majority of cases it is our internal hurdles that hold us back.