The endowment effect, a concept rooted in behavioural economics and coined by the eminent Richard Thaler, is the theory that people tend to assign more value to things simply because they own them.

If you remember Gollum from Lord of the Rings and how he ended up being infatuated by the ring, you’ll know what I mean. Some practical examples in everyday life could include when someone takes a car for a test drive, the endowment effect starts to kick in. Or if you’ve ever lent someone your lawnmower you’ll know exactly what I mean.