Running a service oriented business isn't the same as running a product oriented business. There's a major difference and over the course of time I've learnt where the differences are when it comes to resource tracking, and how that may or may not affect your business.
A story about the risk of over-abstraction and false assumptions on technical debt.
The most important thing with retro's is that you have them. But when you have them, there are a couple of things that you can do to optimize and get the most out of them.