It helps to pick coverage against the things that actually happen rather than the things that make good stories. Here is the shape of it.
Theft, mostly from storage
Machines get taken from open trailers at motels, from unlocked sheds, and from cabins between visits. This is comprehensive coverage, and it is the reason dropping a policy in the off-season is a bad trade.
Hitting something you could not see
Stumps, rocks, and fence posts under fresh snow. Nobody else is involved, so there is no other party to collect from — this is collision coverage doing its job on your own machine.
The trailer
Unhitching on the highway, a blown bearing, a trailer that gets hit while parked. If the trailer is not scheduled on the policy, it and sometimes the machines on it are not covered. It is a cheap thing to add and an expensive thing to forget.
Hitting another rider
Less common, more expensive. This is liability, and it is where minimum limits stop being adequate fast — an injury claim reaches six figures without much trouble. If you own a home, look at your liability limit against what you would be defending.
Gear
A helmet, suit, boots, GPS, and a set of aftermarket skis add up to real money. Most policies include a small automatic amount for accessories and gear; if what you own exceeds it, schedule the difference.