To show up your local joiner, my garage doors are pine, they were old
when I bought the garage well over 30 years ago second hand, and I
reckon it was at least 30 years old then, and are still looking good.

It sounds as if your local joiner needs avoiding for shoddy design and
workmanship

Rob

I bet your garage doesn't face south or west though.
I've worked on houses where Victorian windows on the north side were
still in good nick, and everything on the south side was shot to pieces