One of the skills a writer needs is to be able to get the most out of the words he uses. It is relatively easy to go on at length about something and by doing so convey what you mean to the reader. If I describe something using as many words as possible you will eventually be able to visualise it. If I keep going it will get annoying. Once someone knows what you mean, they will not appreciate your eagerness to be extra super clear.
It is not just a matter of using the fewest words either. Simply stating facts in a literal manner ends up being very dull. But when you can concisely convey what is happening and at the same time evoke an emotion, a strong tone and specific voice, then you start to create something beyond information, you create story.
It is something of an irony that the most efficient, succinct way to get across something that people instantly recognise and relate to is to use a cliché. If I say 'He had a face for radio' you know exactly what I mean and it is a clever way of saying it, and kudos to whoever came up with it. The thing is, it's easy to get a laugh with someone else's joke but that doesn't make you funny. Being an author is about authorship and you want people to know that what they're reading is you, it's your work and your ideas and you should get the credit (or blame).
It can be fun to use flowery or even purple prose and some people may have a preference for that style. It may even be a perfectly reasonable way of writing in certain genres. But if you needed to rewrite it in a more concise manner, could you? Because a carpenter who tells you the hammer is the best tool for the job but doesn't have anything else in his toolbox isn't necessarily the person you want to employ. And there are certainly times when less is more.
If something happens quickly, you don't want to take up pages and pages describing it, you would just end up creating the opposite effect from the one you want. And if a character is of minor importance then describing them in great detail is going to be confusing. The amount of words you spend is going to be taken as a reflection of the importance of the thing that you're writing about. So if someone walks into the scene and you feel it's necessary to give the reader an idea of what they look like, describing every single item of clothing that they are wearing will certainly do that but if after announcing the dinner is ready they disappear and are never heard from again it will seem rather strange thing to have done.
By and large capturing a moment in a few words is a very valuable skill and one that should be exercised whener possible. Although there are times when people go too far in the other direction. When critiquing sometimes it is possible to get so wrapped up in pointing out every possible place where edits can be made that eventually a line as innocuous as "Dave sat down and ate his dinner" will draw the comment that you don't really need to say that they sat down since sitting is implying a downward movement. And standing up, do you really need to say up? These sort of silly over-compensations turn up from time to time but you have to allow for the language as it is used in everyday life. Indeed, leaving room for voice in the narrative means sometimes a little inefficiency is desirable. But again, it should be because you choose it to be that way, not because you happen to have your hammer with you and nobody ever taught you how to use a screwdriver.