Finding the Right Solution – Explore As Many Different Ideas as Possible Within Given Constraints
Iain Barker explains why you should consider more alternatives when solving a problem (in his case, user interface design) rather than trying to optimize the first reasonable solution found. As illustrated in the image below, jumping too quickly into the iterative phase (the phase where you refine a given solution) might prevent you from seeing a better solution.
As to answering the question “how many alternatives are enough?” The somewhat obvious answer given is that it depends on the specific constrains that are imposed upon you, such as time and budget.