One of the key things that prevents progress is bottle-necking. This usually occurs when one person believes they can do everything. The fact is, if you believe this, you are probably wrong. Even if you are right, you are applying a ceiling to your own progress by limiting the output to only what you can produce.
The ego gets in the way. The belief that either we can do everything or we can do everything better than others. I know that my ego occasionally arises in this way. The way that I combat this is by pretending that I can’t do the task at hand and asking myself who I would reach out to if that were the case.
This satisfies the ego and also allows you to make the decisions necessary for the progress of your work.