Reason #1 means the relationship is still on the superficial side. The woman may have decided to kick it up a notch, but missed and accidentally made contact with the man's scrotum.
It seems to be generally accepted that women are not always ready to have sex when men are. Isn't it possible that men may not be ready to stop having sex when women are? These are two sides of the same sexual coin, as far as I'm concerned. (I picture one of those tokens they use at the peep shows.) For women, it's a sign of emotional closeness to have sex with a guy. For men, it's a sign of emotional closeness to stop having sex with everyone else.
If the relationship is ten years old and the guy is still worried about the lack of variety in his bedroom, then he probably shares some of the responsibility for the quality of relationship not elevating beyond the superficial. Therefore, it may be up to the woman to determine whether reason #1 is at play, and whether there's anything she can do to improve the relationship. (Unless, of course, she's perfectly happy with the relationship as it is.)
Reason #2 why men don't commit is what many women are afraid to acknowledge. It feels much more comfortable to attribute the man's resistance to an imaginary "fear". However, I don't think most men are afraid of commitment. What they're afraid of is being treated as a security blanket. Just like women, men want to be treated as objects of attraction. That's how they feel at the start of a relationship but not necessarily at the time a woman asks him to "commit".
A lot of men are completely willing to commit - until the moment a woman asks him to. The reason is because when she asks him to "formalize" the relationship, the man sees it as the act of flushing all the sexual energy down the toilet. The idea of being treated as a security blanket is repulsive to the man's sexual nature, unless of course he's already allowed the woman to rip his proverbial testicles off (or he's given them away after a string of failed relationships) and he's now ready to commit sexual suicide.
