Answer : The scientific theory is considered to be the foundation of many science experiments because it has well supported theory related reproducible data of test table, experiments,etc. which are usually valid and is of great help in predicting reactions.
Also these scientific theories are considered to be robust, durable and can be changed as and when required; because of its flexibility in accepting a modification/change or addition to the previous theory. All of these reasons contribute to develop scientific theories into a stronger and longer durable one.