With your own authority, unless you have really deep pockets, accidents start driving up the cost of your insurance with the first incident.

An independent can not afford to be having accidents of any type, if they plan on being in this business and making money.

Frequency and/or loss ratio drive up cost.

There are a lot of Shipper's out there who use the "Safe-Stat" ratings to negotiate the rate they pay a Carrier. It is hard to get the high dollar rate, when you have a crap safestat score!

Many won't use you unless you have a satisfactory rateing.

True...but if you have a "high" satisfactory rating number.......you may well end up getting a lower rate per mile, from some shippers, than the carrier with the "low" satisfactory rating will get.

Just one of many factors used.

Yup. But they use every tool available to drive down that rate.

Their business to do it as cheap as possible,trucks to do it as high as possible. Usually meet somewhere in-between.

An O-O having accidents is akin to a restaurateur giving diners food poisoning... find another line of work!

Just for thought:
Non-preventable for the O/O
Supplier contamination for the restaurant

Both can put you out of business by default.