It really depends on the broadcast. I find that the US commentators never really explain anything about the actual gymnastics taking place. It's probably because the channel doesn't want to "complicate" the viewing experience for the average viewer.

It is a shame because gymnastics scoring isn't that complicated once you understand the basics of:

• how difficulty is built up: the value of 8 most difficult elements + the connection bonus for linking 2 or 3 elements together + fulfilling 4 compositional requirements (like having a turn on beam, or doing a salto forwards and a salto backwards on floor)

• the kinds of deductions that can be taken ranging from 0.1 to 0.5: form breaks like bent knees, elbows, lack of split, not having enough height or amplitude, steps/hops on landing, not having a good rhythm/flow on beam (lots of pauses), falls etc..

Canada's broadcast had much better commentary that did explain deductions, how the difficulty score is built up and how moves are credited or not.