“There are several reasons”
That’s another way of saying, “It’s complicated.”
If you’ve got one reason that’s good enough, share that reason. The other reasons are extra, and if you spend a lot of time on them, you’ve just told us that it’s complicated.
Difficult decisions, on the other hand, ARE nuanced, and they involve adding up several benefits to overcome several negative outcomes as well. In those cases, it’s worth beginning by highlighting the things we’re going to avoid as a result of making this choice.