TPM's core idea is that the person running a machine all day notices a new noise or a loose guard long before a maintenance technician on a scheduled visit ever would — so TPM trains operators to handle basic care and early-warning inspection themselves, freeing maintenance to focus on the work that actually needs a technician's skill set.
It's most associated with OEE as its measurement framework: the goal of TPM is directly moving the availability and performance components of OEE, by catching the small issues — a jam, a misalignment — before they become a stoppage.