Buy an old Windows laptop and you’ll probably be able to keep installing Windows updates until you decide that your system doesn’t have enough RAM or a fast enough processor to meet your needs anymore.
Buy a Chromebook and the clock has already started ticking on software updates.
Google guarantees to deliver OS updates for a set period of time for each new Chromebook that’s released, and after that you’re stuck running software that may no longer have the latest features or security updates.
The good news is that Google keeps extending amount of time for which software updates are guaranteed – two new Chromebooks announced this month will be the first to receive almost 9 years of support.

The HP Pro C645 Chromebook Enterprise and Lenovo ThinkPad C13 Yoga Chromebook Enterprise will both receive updates until at least June, 2029 according to the Chrome Auto Update Expiration policy website.
These Chromebooks are some of the first to feature AMD Ryzen processors, and both models were launched in September of 2020, which means they’ll be supported for more than 8.5 years, and possibly for longer than that (Google has been known to roll out updates for a few months after a Chromebook hits the end of life from time to time).
Odds are that by the time 2029 rolls around, you probably won’t be using a Chromebook purchased today anyway since the hardware will probably be rather outdated and the battery life rather subpar by then.
Extending the lifespan of new Chromebooks is a good thing, since it could help customers keep their hardware for longer without exposing themselves to unnecessary security risks.
When the first Chromebooks were launched, Google only promised 4 years of updates, but over the past few years we’ve seen that number inch upward a little bit at a time. But it doesn’t affect the Auto Update Expiration (AUE) policy of older models that have already been on the market for a while.
But having an end date at all is still kind of a problem for folks who may be buying refurbished, used, or B-stock Chromebooks. Now that Chromebooks have been around for a while, retailers are often running sales on older models that have either already stopped receiving updates or which may have a year or less of updates left to go.
via Android Police