Since theories can have similar components but also be completely different, it is likely that not every theory will fit with every person's idea of how something happens. One theory could fit what one person thinks about a certain issue, while another theory could fit what a different person thinks, although one theory could be more correct than another.
Many theories are formed to explain only one thing, they are "pigeonholed" and cannot be adapted to fit new ideas very easily. If one person observes one thing and they create a theory out of it that explains what occurred, someone may come along and view two things that occur and create a theory that explains it better. The more observations a person has, the wider of a range their theory can encompass, because it can stretch to fit other situations than just one. Also, a theory developed over a period of time, like the atomic theory, can change to fit and reflect new discoveries without completely erasing the fundamental parts of the theory necessary for it to be convincing and fit situations. Parts of Dalton and J.J. Thomson's ideas about the atom are still found in the atomic theory. Parts of theories can also be found incorrect and modified to be correct.
I think it is not bad to have multiple theories in order to explain or show one thing, but I don't think that it is good either. Theories with multiple observations that can fit several scenarios for one thing better than the other is, in my opinion, the better theory. It is important to be able to be flexible when considering how one theory fits another so that one is able to make the decision on their own.
