Master new skills or improve the ones you already have. In each progression the exercises go from simple to hard. Quite likely you are no longer at the very beginning, but even so, completing a progression in full can take a long time. If you want to master a skill faster, build a program around that skill.
Progressions are grouped by the nature of the movement, by muscle group or by equipment, and sorted by difficulty. Turn on automatic recording of your workout results in the progression ladders if you do the exercises they include.
Muscle Train is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.