Multiple software engineers working to solve the same problem in isolation will arrive at different solutions. Some may work better than others, but that's irrelevant; what's important is that these different engineers will have all achieved a complete understanding of the problem and its solution, and when they collaborate on a new, more complex problem that builds on what they've already done, they each bring their own unique perspective to the table.
This is why side projects are so absolutely crucial to a software engineer's mastery of his or her craft; by working through a problem alone, the engineer not only gets a better understanding of the problem, but is also able to apply diversity of thought to a team's problem set.
I eventually started thinking of side projects as the software equivalent of "practicing my chops" as a musician. It doesn't actually matter that much whether all those free-time experiments ever become shippable products - and most of them not only don't, but couldn't - so long as the process of working on them helps me stretch my knowledge and keep my skills sharp.
Multiple software engineers working to solve the same problem in isolation will arrive at different solutions. Some may work better than others, but that's irrelevant; what's important is that these different engineers will have all achieved a complete understanding of the problem and its solution, and when they collaborate on a new, more complex problem that builds on what they've already done, they each bring their own unique perspective to the table.
This is why side projects are so absolutely crucial to a software engineer's mastery of his or her craft; by working through a problem alone, the engineer not only gets a better understanding of the problem, but is also able to apply diversity of thought to a team's problem set.