Put another way, a good thesis sentence will inspire (rather than quiet) other points of view. One might argue that America is violent because of its violent entertainment industry. Or because of the proliferation of guns. Or because of the disintegration of the family. In short, if your thesis is positing something that no one can (or would wish to) argue with, then it's not a good thesis.
That means it is not all advisable to even suggest something as a good thesis sentence without factoring in the nature, method or in fact, the purpose of a thesis. Purpose, or the aims and objectives, of the thesis can only be formulated if one is smart enough to dig up a little information on the thesis topic. Even then one should not expect to arrive at a ready-made jolly-good thesis sentence. So, what next?
Dissertation process timeline -- Good thesis sentences - Temizlik
The above observation illustrates how one can arrive at good thesis sentences like “The best time to innovate is during recession”, which is, both, assertive as well as illustrative or simply, the exploratory “Is recession the best time to innovate?”. This was done by taking into consideration one aspect of the research i.e, the best time for innovation. One can chose one or more (as the case may be) such aspects in formulating thesis sentences, as indeed the dissertation work.