I have a habit of speech — acquired long ago and hard to shake — which is the unnecessary use of prepositions in phrases like “hurry up” and “stand up”. I don’t write that way, but I still (too often) speak that way.
I hadn’t been conscious of the habit, probably acquired from my Midwestern parents, until about 30 years ago when a young computer whiz corrected me when I said “open up”. She said that “open” would suffice, and my eyes were (figuratively) opened; that is, for the first time in my life I understood that I had long been been guilty of preposition proliferation.
In addition to “open up”, “hurry up”, and “stand up”, there are “fill up”, “lift up”, and possibly dozens of others that feature unnecessary prepositions. I leave it to you to list your favorites.
There are also phrases involving prepositions that aren’t quite wrong, but which are unnecessarily long. Consider, for example, one that is used often: “come in”. It’s really a shorthand way of saying “come into the room/office/house to which you are seeking entry”. So the “in” isn’t superfluous, but it is unnecessary.
“Come” will suffice, as will “enter”. Why aren’t those expressions used as commonly as “come in”? I suspect that it’s because “come in” sounds less abrupt and more cordial than the peremptory “come” and “enter”. That is to say, “come in” is more welcoming.
Which brings me back to “hurry up”, “stand up”, and similar phrases. Perhaps the prepositions were added long ago to suggest that the speaker was making a request, not issuing a command. That is, they were added out of politeness.
Perhaps it is politeness that prevents me from giving up abandoning the practice of preposition proliferation.