All of those come down to "Let the compiler guess about my data, and it may produce correct results in some of the cases."
A risk is, unexpected data (empty field instead of zero; a real number introduced in untested corner cases where only an integer will actually work etc) can cause issues after deployment.
Those 'complex' requirements mean, if you want a reliably correct program well then you'll have to put in this much work. But go ahead, that 'trivial task' may become something less trivial when your task fails during Christmas sales season or whatever.
A risk is, unexpected data (empty field instead of zero; a real number introduced in untested corner cases where only an integer will actually work etc) can cause issues after deployment.
Those 'complex' requirements mean, if you want a reliably correct program well then you'll have to put in this much work. But go ahead, that 'trivial task' may become something less trivial when your task fails during Christmas sales season or whatever.