The Technics SL-1200MK7 is a direct-drive turntable used by DJs and hi-fi listeners, often seeing physical wear from transport, cueing, and dust exposure. Failures tend to be mechanical/electromechanical: tonearm bearings, switches, speed control electronics, and power supply components.
Repair is typically sensible because parts are often serviceable and the deck's value is durable-especially when issues are limited to switches, tonearm setup, or a control board. Replacement becomes more rational only if the platter motor/control system is severely damaged, the tonearm assembly is beyond economical repair, or repeated damage occurs from heavy gigging.
Price referenced from Technics' product listing; lifespan uses a conservative home-technology expectancy, acknowledging that careful owners can keep turntables running far longer with maintenance.