Years ago I had an Admiral side by side that leaked right after the warranty was up. A friend told me to look at the drain tube, and sure enough it was plugged by some paper from the factory.
Fast forward, last year my Hotpoint leaked. A quick look at the drain line and sure enough it was plugged too with some debris.
I assume that during assembly, careless workers cause these things to eventually cause a leak. low quality control? sabotage? frustration? low pay? who knows.
John, you don't need to install a floor drain, that's absurd. Just keep the back of the fridge clean and watch for ice build up - a sign of water in the wrong place. Regarding what your repairman said about this happening every 2-3 years - it's not a rule.