personally i feel teams don't score because either their forwards have a bad day or the goalie plays amazing, i find it very rare for a defence to dominate and be the strength.
When it seems that is the case it is in fact the issue of the team who does well having their midfield dominate. the midfield either control the ball or stop it getting to the defence.
I feel you very rarely see instances where there is a well drilled defence who dominate the ball, this frustrates me, hence shown by the numerous high shot/chance games we see in fm
i would prefer to see less great goal keeping performances and more where your defenders play like rocks, which is also much more often in real life. for example in the epl david de gea is the only goalie you could say has been brilliant on serveral occasions for his teams. whereas you could list numerous defensive units