For all that we'd like to believe in our rational choices, there is too much unknown and unknowable. We tend to favor products that would have solved our recent issues had they been in place (and yet not be sure about how they'd handle our unknown future crises). We tend to choose products that make sense to us as IT, but might not make the same sense elswhere in the organization. We cannot tell how it will scale in reality, how people will accept it, and how it will handle unanticipated needs.

And every major product or project subtley changes the company down the road, a kind of 'butterfly flapping' event. It tends to channel users in directions where that product, by nature of it's philosophy, steers them. That, mixed with the unpredictable impact of outside forces in a continuous feedback loop can mean that we'll get to a somewhat different place. But we simply cannot predict what that place is for any product.

In the end we can agonize indefinitely. Better to choose a qualified product and run with it.