I always wonder whether anybody is really changing geyser anodes regualarly? What do you do?

The geyser is a funny thing. Nodody really has a hightened vested interest to make it last in my view.

The manufacturer only needs them to make them last past the warranty. The sooner it fails after that the better. I have seen geysers not even survive the 3y warranty. Kwikot are the worst in my view.

The plumbers make more money the more geysers they replace/repair.

Insurances factor it in anyway and get they money in the end by pricing the premium accordingly and/or just impose a bigger access to soften the "hit".

Owners just pay the access and expect to pay it every few years. So owners also factor it in and its not hurting them too much.

So will changing anodes make any difference?
How much does that exercise cost on average?
How often should one replace them?

I ignored the following points here:
- most people do not even know about anodes
- drain on the environment due to old geysers/parts, travelling to and from site etc
- whether the switching on and off vs leaving it on permamently makes any difference to the geyser life/elec consumption
- resulting damages due to leaks often due to substandard installations e.g. no or faulty drip trays