Because getting it "almost right" just isn't right.
The best any aftermarket company can do is provide you with almost right parts for your Exmark mower. Those parts may look right, feel right, and may even seem to fit right. But when it comes down to making your Exmark machine hum like no other, only Exmark has the expertise and knowhow required to get it precisely right. Every time.
Exmark won't stand for "almost right" in anything we do.
The truth is, nobody knows your Exmark machine better than the people who developed it. No aftermarket parts provider owns the original design, engineering and test requirements needed to make meaningful, original quality claims. So, if you don’t use Original Exmark Parts on your mower or turf management equipment, it's not 100% an Exmark.