i get that part to a point, but from a business stand point you want to try and get as much momentum as you can carry over into those titles. which they've set up very well with Thor over the last year. however, lets say you pick up Thor and like it and wanna try out FF, becuase you enjoyed the movies, but when you pick the title its no longer Fantastic becuase they went and killed The Human Torch, and he was the guy you liked. after that you don't bother with comics anymore cuz it don't make sense. and have lost all momentum to sell more comics to people.
becuase marvel also has to many mini-events that they also kill people in that you don't know where to start, therefore also losing your carry over momentum.