For me, it was that I never kept any of my other bikes long enough to go out of warranty or the bikes I had didn't cost $20K and have complex systems. Also, this is the first motorcycle where I actually planned on riding it for an extended period -- 74,000 miles and still ticking.
I purchased a Pinnacle Extended Service Plan shortly before my BMW 3 year/36,000 mile warranty expired. I forget what it cost exactly, but I know it was less than $1000. To date, Pinnacle has:
Replaced my rear drive: $950
Replaced my ABS hydro unit: $3500
Replaced my rear main seal: $750
So for an investment (or bet) of less than $1000, I have had Pinnacle pay off on $5200 in coverage. Sounds like a good investement (or bet) to me.