Any thoughts on why some leaves on my orchids have holes?

Looks like snail or slug damage to me. Edges of those holes are dry though, so it doesn't look like it happened recently.

If you see any new ones, I'd make a thorough search for the little slimy critter and roust him out.

Around here in Summer, Crickets can take a good bite out of a Phal leaf.

Ursula, is it possible to consolidate all these stray threads popping up lately?

I know what you mean, Roberta.
Unfortunately I am not able to combine them, I asked Dave.
I can only advice people to post into existing threads, once they do that I am able to delete those extra threads. The other day I addressed this and got nowhere.
I wish people would realize that starting for every post another thread does not guarantee that people actually see it. It happens quite often that I didn't see a new thread, until it had already several additional comments. By that time it is a bit late to ask to repost. This time I chimed in too.
Our monthly bloom threads are fun and chatty enough that one shouldn't be afraid to post a special bloom into it with a comment.
So, all, would you please be so kind and look through our existing threads and see if they can't simply be continued with your post? If you want others to see your post, your best bet is to not start a new thread unless it truly honestly something very different.
And Roberta, thank you!

Oops, my bad. Thanks to you, I learned about Brassavola Little Stars and Dendrobium Zeuxine.

Lisa, you are forgiven! If it happens again, we need to send you an Orchid!
But - I hope you can see the reasoning?