Question

Scientific theories can change over time as new information is discovered if a scientififc theory changes does this mean that it was not a good theory to begin with?

Answer 1

Not necessarily, it just means that the Scientific theory was not complete and needs additional information, research, and ideas. 

Answer 2

The correct answer to this open question is the following.

Scientific theories can change over time as new information is discovered. If a scientific theory change this doesn't mean that it was not a good theory, to begin with. What means is that science is permanently researching for new and better ways to do things or to understand natural phenomena.

With discoveries, science can apply new methods of study and get relevant and new information that later could be changed if something new is discovered. That is a good part of science. that is always researching to innovate.