The wear on a rim is going to be due to a variety of sources: the kilometers, abrasion of the braking surfaces, corrosion, crashes etc…
All respectable rims are made of aluminum, which does have a finite life, as aluminum does not have a fatigue limit. However, that fatigue limit could be reached at 2000km. or 50.000km depending on the cross-sectional shape of the rim and how heavy it is loaded. The only way to know this is to inspect.
As for the brake track and corrosion, riding around exclusively with clear skies in the summertime of Italy will have a much different impact on the rims and spokes than someone riding year round in Holland in the sand. Getting sand and other gunk caught in the brake pads can wear the tracks significantly more than in clean situations +/- after 5-6.000km. Road salt and other substances can corrode the spokes and cause wheel failure through that.
In short Lightweight super-nice-crazy-expensive-pro-racer wheels that are only used for a few rides or +/- 3.000km before being discarded are not for everyday use.
12 – 15.000km should be the standard lifespan of what a good wheelset will be capable of delivering.
Also remember not to clean your cassette with any fat removal or pressure water pipe while it is on the hub.
Don`t use a pressure water pipe or any fat removal to clean your bike and chain while the wheels are on the bike.
You can clean the wheels with water and dishwasher and rinse them using the light-shower setting on your garden hose.