Earlier quoted context omitted.
For fun, listen to David Cassidy's work during the Partridge Family years, when the studio wrote the songs and provided musicians for him, and compare to Cassidy's post-PF work. What, you never heard of his post-PF work? :-) It's because it's awful. Ditto the Monkees. At least Cassidy could sing (and damn, he was good). The Monkees couldn't write, sing, or play without massive help.
Actually, two of the Monkees were in bands before their "acting career" and they performed live together without assistance. They broke up because of a no-holds barred fight with their producer/svengali, declining sales and an awful vanity film (think Spiceworld but much worse), but their albums still sold.
I bought one of their post albums where they wrote their own songs and played their own instruments. Sorry, it's just awful compared with the studio produced albums. Nobody remembers those songs for good reason.