When you buy software or services the goal is to not just have an incremental improvement but to do significantly better. You don’t buy software that costs more than what you gain (and yes, gains can be non-financial for this purpose).
With that in mind, looking back at your past vendor decisions, have they made you a better company? Are you getting what you wanted and recognize an ROI?
If you are, great – keep at it. But if you aren’t, why not? Did you have wrong expectations? Did the product or service do things differently than you were told? Was your problem different than what you thought it was?
It’s important to look back and understand whether you make decisions the right way or not.