Science knowledge relies on experimental and observational confirmation. Where data is incomplete, new or improved data may well lead to revision of accepted science explanations.
Revision of any scientific concept is based on scientific knowledge that has been experimented, tested and confirmed through observation. For instance- any scientific concept that was lacking complete data set (unknown at the time of its explanation) , but now new or improved data has been established which shall lead to revision of accepted science explanations.
In most of the situation where a scientific concept is updated consists of data sets that is fragmentary and hence a bit of incomplete.
