Oh, I agree that under normal circumstances, the condenser coil being dirty wouldn't cause ice buildup, but with how incredibly overengineered Samsung makes their brown-goods, I wouldn't put it past them to have some sort of circuit that would cause frost buildup in the freezer. They really need to stick with phones, tablets, TV's and wearables, or dramatically dumb-down the controls for their refrigerators, washers and dryers, and other appliances. But yea, my bet is the defrost board...

I've heard the same thing about LG's as well. The overall consensus is that they've made them far too complex to the point if a single, small, generally insignificant component fails, the whole system shuts down. I had bought an LG Inverter window AC last year to bide my time until I replaced my heat pump, and that thing had over 100 points used for its diagnosis board, ranging from probes for the temps and pressures on the high and low side, air flow, and a bunch of stuff that was redundant. While yes, it's an inverter unit, it doesn't have to be made that complex! I'll stick with my now 18-year-old Frigidaire refrigerator with its simple design that the only thing I've had to do so far is replace the water switch and motor for the ice maker...

The good thing about Whirlpools is that they've been making fridges forever, parts are easy to come by, and they're simple compared to the Samsungs and LGs. I'm running an 18-year-old Frigidaire that's still running like a champ that I picked up from Lowes scratch-and-dent section, fortunately the scratches and dents are on the side that isn't visible where I put the fridge...

Appliances in general are fucking nuts now.

Source: just had to get a new fridge and am shopping to replace my slide-in range. Solidly in "goddamn" territory cost-wise.