Even with the best of intentions, product roadmaps typically lead to very poor business results. I refer to the reasons for this as the two inconvenient truths about product.
The first inconvenient truth is that at least half of our product ideas are just not going to work. There are many reasons for a product idea to not pan out.
Sometimes customers just aren't as excited about this idea as we are, so they choose not to use it or buy it (the value isn't there). This is the most common situation.
Sometimes they do want to use it, and they try to use it, but it's so complicated that it's simply more trouble than it's worth, which yields the same result—the users don't use it (the usability isn't there).
Sometimes the issue is that the customers might have loved it, but it turns out to be much more involved to build than we first thought, and we simply can't afford the time and cost to deliver (the feasibility isn't there).
And, sometimes the issue is that we encounter serious legal, financial, or business constraints that block the solution from launch (the business viability isn't there).
If that's not bad enough, the second inconvenient truth is that, even with the ideas that do prove to be valuable, usable, feasible, and viable, it ...