rls8, invariably the answer should be "no", otherwise why are you applying at all?
I think the sort of thing they are getting at is this .... say someone is a doctor .. and then they are struck off the medical register for some reason .... well such a person should answer "yes" to Q10.
It is often the case that questions are included to make it easier to revoke visas should it later turn out to be the case that the person lied on an application form. For example :-
Have you ever been involved in the financing, planning, preparation, commission or attempted commission of terrorist acts or in supporting acts of terrorism either within or outside the UK or have you ever been a member or supporter of an organisation which has perpetrated or supported acts of terrorism in furtherance of its aims?
Anyone with even half a brain would realise that if they answer "yes" to that question, well they are not going to get their visa, are they! But if it later turns out to be the case that their "no" answer was wrong, it is easier for their visa to be revoked.
I think the Q10 you mention is that sort of question.