How to define the value of Help Desk and CM software to the execs

I am in the throes of implementing an enterprise level help desk and change management suite and am having issues showing executive staff the value and reasoning behind going this route. I’d like to hear anyones business case on the pros and cons of implementing such software in an up and coming company.

I have a signed PR, but I want to make sure that executive staff fully understand the value and the benefits.

Thanks

Steve