It's a clear signal, the company values you less than when it hired you. When leaving a company like that I find it best to frame it in a way that they were unhappy with you. "Hey look I know you are trying to spare my feelings, but that is 6 percent less than inflation, clearly you want me out of here but didn't have the courage to lay me off. Thanks for the heads up, I've found another role."

I started at a company in mid January, and they did annual reviews in June/July. After review, I 'merited' a 4% raise. But... because I'd only been there since January, they prorated the 4% raise to 2%. I never quite understood their logic, but also didn't stay through the end of the year.

EDIT: this was... 2004/2005 era.