User blog comment:StrategicMagic/Carry by Proxy - Why (Some) Assasins Don't Fall Off Late/@comment-83.244.229.222-20121206213114

LB's damage before MR does not match late game that of other APs, and that it is single target means a team able to co-ordinate and hide behind target's not worth engaging are hard to beat this way.

Eh. People like Ori and Kat outscale in damage output and poke, have more utility (likely damage from all of their toolkit) and fight at a safer range, whilst complementing the current AoE meta. Still think LB falls off, not late game but teamfights - it's just that those happen more, and are more decisive, late game.