Astronomy Question:

This often confuses people that there are stars that have been through their entire life cycle yet there are many stars still forming.

Well part of the answer is that a large star burns quicker and dies quicker so might have its whole life cycle in the fraction of the time a star as if our own Sun does which is perhaps mid sized.

Therefore, it might take a billion years for a large star to go through its lifecycle and if stars started to form around a billion years after the big bang, then after 2-3 billion years stars could have burnt out, thus they could have died already.