Why are Pro Formas so misleading?

[Nic S.]

Maybe this is more a vent session but being a new investor I'm shocked that Pro Formas are as misleading as they are.

I'm dealing with sellers who are selling to investors but their Pro Formas are written as if they were selling to consumers. A classic example is interest rate, as an investor the low bar is set at pretty much 5%. Yet, these Pro Formas are showing rates from 3.8% - 4.8% 

I don't understand why investor centric sellers try to fudge the numbers in an effort to make their returns higher.