hugh51271 and oman112 both post questions about what is commonly referred to around here as a "divot" on the sleeve, and ask if this has anything to do with the shoulders being too wide, and the answer is no. Divots have nothing to do with the shoulder width. Here is a gross oversimplification:
The sleeve must be drafted in a size and shape that relate to the size and shape of the armhole. When the garment fits correctly though the chest (that includes, most critically, across the back) the sleeve will fit correctly.
If there is tension in the chest, the garment will pull, compressing the armhole. It gets shorter and wider. The sleeve, however, has not changed, so it will pull, and the excess cap height in relation to the armhole height will result in the divot.
We can see where hugh's full blades are pulling on the jacket- this tension is pulling the armhole and sleeve out of shape.
There are a few other, more arcane things at play here, but the gist of it is that. In most cases, if there is a severe divot, it can not be fixed. Minor ones can sometimes be fixed but you need to be seen, in person, by a competent tailor to get a proper assessment. Since it involves removing and resetting the sleeve, it won't be a cheap fix either.
Thank you, jefferyd...
These are all things that I see but simply don't have the time in to communicate certain problems quite like that. Learning experience over here, too!