small table is made but not learned
I made several small tables, but large table keep locked.
And happened to be unlocked when nobles are ordered to crate multiple of small tables.
I found nobles learn small tables while crating, then large table was unlocked.
So it should mean small table was not learned while made
It's possible that the person why made the small table was unassigned from building if you had someone else joined. It's also possible that the person who made the small table didn't have enough skill to learn the large table.