They need someone to write interesting songs to create a context for their lead skills.
I was in a band with a lead guitarist (I played rhythm and sang), who could play just about anything, and create amazing original solos...but he couldn't write songs to save his life.
I wrote a few songs, some with our bass player, that he rejected. Things weren't going well with his originals, so we had a band meeting. He told us (rest of the band)) that he was the band leader, and wanted to be the only songwriter, and even wanted to change the band name to use his name. We all quit on the spot, and formed another band, and found another lead player (good lead guitarists were plentiful) and did better, and had a few originals in our set that we all enjoyed.