On a couple bikes I have the stem angled down instead of up to avoid cutting it, that makes the bike look better with fewer spacers above the stem. For a while I had a 17 degree stem on my Sherpa to help minimize how many spacers i have above the stem, see photo.
I do not want to cut it because if I sell the bike later, a buyer might want the bars higher. Exception - My Nomad, I cut the stem because it made it easier to pack the bike in an S&S Backpack case. I think I cut the stem three times, each time leaving it a bit longer than where I thought it should be cut to avoid the danger of cutting it too short. And several months between each cut to make sure I was not making a mistake.
If you cut it yourself, the way I do it is I wrap a piece of tape around the steerer so that the edge of the tape marks where I want the cut to be. By putting the tape on it so that the tape is exactly perpendicular to the axis of the steerer tube, then being careful when I cut it to keep the saw cut at the edge of the tape, I make sure that my cut is not at an angle.