Player Promise "Will develop player"

[hxp]

What does this promise actually mean?

I'm trying to sign a young player on a free and he wouldn't accept to be a backup player without this promise.

To be exact: Will develop player, will give player playing time next season (player will expect to play next season).

For some reason i can't choose the other options that are usually available like finding a loan or play in cup games but i think that's a Ligue 1 thing.

Will he expect to play A LOT even if his agreed squad status is only backup? Would i be better off to just promise him to be a rotation player without promising to develop him?

[enigmatic]

Much better to promise rotation squad status 

That promise doesn't stick around and you can downgrade him to backup whenever you like after signing him.

The other promises are, at best, buggy and at worst utterly ridiculous.