No it's not.
You get taxed on the increase so you actually become poorer each year if you get CPI related increases.
Too many years of that and staff end up having to resign to look for better paying jobs.
Care to back that up with some actual maths?
Let's use a 30% tax rate.
If you earn R30k a month and pay R9k tax = R21k "out".
10% increase, it becomes you earn R33k a month and pay R9.9k tax = R23.1k "out" .
R21k -> R23.1k is a 10% increase of what you get out.
Unless all or part of that increase falls into a higher tax bracket, a 10% increase in your gross will result in a 10% increase in your nett...
I've never understood why people feel entitled to above inflation increases. Sure, depending on your field the first few years your productivity will increase, in which case so does your value and then it's not unreasonable. But just because you've been doing a job for 7 years doesn't automatically make you 3% or 4% more productive than when you'd been doing it for 6 years.
I work in IT - I've seen plenty of people price themselves out of jobs with the "I'm a hotshot - give me 15% or I walk" attitude. Quite a few of those leave only to come back, hat in hand 6 months or a year down the line. (And no, my company isn't stingy).
When it comes to normal, annual increases, we start out at inflation and from there it's a spread of about 2% either way.
Performance or promotion based increases are a different matter entirely, and handled outside of the annual increase cycle.