During the systems development life cycle , certain key problems discovered in the later stages could be directly traced back to inadequate and/or

During the systems development life cycle , certain key problems discovered in the later stages could be directly traced back to inadequate and/or poor efforts in the requirements phase and industry studies show that over 50% of systems problems belong to this case. In addition, as mentioned in this week lecture notes "the cost of errors in requirements that weren’t discovered until later" may go up to 1,000 times. As a systems analyst, what should we do to minimise this problem? How might this be avoided? 200 words and a reference.