One of the key features of depression is the lack of motivation to do things that you know you should really do. Depression is a vicious cycle. It includes avoidance, isolation, self-criticism, perfectionism, and hopelessness. 

We can add lack of motivation to this vicious cycle because when you lack motivation, you end up not doing the things that you need to do to build self-esteem, to overcome avoidance, to build your support network so that you don't fall into a rabbit hole of hopelessness.