Her skills might be forced on her, but I got the impression that she got out of the Red Room, and then chose to use them (made a name for herself, didn't care who she used her skills for, etc), and it was that which lead to SHIELD tracking her down. If she'd just vanished and found a quiet job, I don't think SHIELD would really care. But she chose (as I see it) to be a free-lance assassin, and she chose to make that name, and that to me speaks of ambition (among...other things admittedly).