To refinance using the IRRRL (VA streamline refinance) program, the new loan must have a lower interest rate or lower monthly payment. The exception is when you refinance from an adjustable-rate mortgage into a fixed-rate loan. Either way, the VA assumes that the refinance is a good idea because you're getting a lower rate or the predictability of a fixed rate.
A VA cash-out refinance requires you to pass the Net Tangible Benefit test. To pass the NTB test, the refinanced loan has to save you money or switch from an ARM to a fixed rate.