As suggested by Vastman, Liam was Noel's Kryptonite. Noel was not only the better singer but also had more creativity. His collaboration with Goldie and The Chemical Brothers suggested Noel wanted to be more creative and try new things but unfortunately Liam was having none of it and they just plugged on with the then tired Oasis.
When the split was announced I expected Liam to do exactly what he did, form an Oasis tribute band and Beady Eye was just that.
Noel on the other hand looked to have finally broken free when he formed High Flying Birds and attempted to change his musical direction. There was also talk of a collaboration with Amorphous Androgynous which would have seen Noel become a lot more risk taking, a bit like his once creative nemesis Damon Albarn. Unfortunately the plans for the AA collaboration seemed to have been scrapped and now an Oasis reform is being talked about. It seems it's too late for Noel to take the risks he once looked like taking. Sad really.