Everytime I install a new motherboard into a case I have problems with aligning the board to the stand off screws.
I don't do it very often, once a year or so.
But I often find that its hard to get the back plate to sit in nicely and to align all of the holes.
Sometimes I have to leave a hole without a screw, which I don't like to do.

I don't think that those cheap black stand offs they give us now help either.
Luckily I have kept a few old brass ones, so I will use those next time.