How to find end-of-life for a laptop?

Before making the purchase, how & from where/whom one should get to know about the expiry/end-of-life of a laptop? Let's say, I need to find it for Lenovo B590-59390111.

No such data is available, I have an HP Pavilion DV9000 that is still going strong since 2009. Others find that the laptop fails much sooner than this.

In general I would expect at least 3years use before expecting some failure
HTH
David

My 3 year old Lenovo G555 laptop has had 3 motherboard failures. Not going for a 4th. That pretty much qualifies as an "end-of-life" notification.

The information regarding end of life or product life-cycle of Lenovo products is generally unavailable
to the users unless it's made official by the company.
Though you can assume the average model lifespan for Lenovo ThinkPads is 18-24 months.
So if you know when it was introduced, you can count on its availability for that period of time in most cases.
Under spl. Circumstances you can contact their production exec. Justifying your reason for knowing the info.