What bonus?

What is it with all these ridiculous offers from car insurance companies that will "protect" your no-claims bonus?

Surely it defeats the entire purpose of the bonus? It's meant to act as an added incentive for careful driving. No accidents (or at least claims) means your no-claims bonus goes up which, in return, helps reduce your premiums when renewing.

Surely having a scheme that attracts customers by protecting something that encourages safe driving is self-defeating? People will no longer strive to keep their no-claims bonus going since it's now "protected" whatever happens. This then renders the bonus redundant, and could even make some drivers less careful when driving.