It's tricky to know who's the iconographer (artist) behind these icons—as it's commonly only addressing the monastery/place who commissioned them.

Is it a common practice/norm, or is there some context that I perhaps miss here?

Pixels, designer, builder · /mek /oldmasters /newmasters · mek.gallery

I believe the „artists“ where often monks of the same monastery. While they surely had a personal style (and most likely different abilities), I don’t think the idea of the artist as an individual was already present.