Members moaned about this 'problem' on FM10.
'Clear cut chances' doesn't mean missed a sitter if you are judging your post game stats. And if you are going by the 3D match engine, its merely the game attempting a graphical representation of the processes being carried out in the background, so something that appears to be a golden opportunity to score a 1 on 1 may be a harder chance than it appears. The striker could be off balance, under pressure from a defender, etc etc.
Also a striker needs more than jsut a high finishing attribute to score a one on one or a cear chance.
Composure, technique, anticipation, agility, decisions and first touch are all highly important attributes when it comes to scoring a one on one or an instinct chance.
There are ways to fix this, some members found success with asking players to time waste more, meaning players take their time over a one on one, not the intended point of time wasting, but hey ho.
Also there are some effective touchline shouts and PPM's that can be used to improve this problem.