Pure Top down only works for small problems or problems you already know how to solve. Its main issue is that you don't know whether the solution is correct unt

Pure Top down only works for small problems or problems you already know how to solve. Its main issue is that you don't know whether the solution is correct until you reach the bottom. Structured Design, which is a quasi top down method, works better in real life. Its main issue is that it didn't survive the OOP hype.