What is the warranty?

It is important to protect the end user. if a certificate was mis-issued to a fraudulent site, and that fraudulent site has an ssl link with an end user and as a result of this the end user loses money. the end user had what they thought was a "trusted session". comodo should never have provided the fraudster with the ability to engineer this situation. hence, comodo has taken out insurance to pay out money to the end user. How can they do this?

Comodo company does value the end customer.

They believe the insurance provided greater peace of mind hence allows the merchant to sell more products.

Most importantly, they value their validation techniques.

Comodo provides validation that is far higher than some other SSL providers. Some CA's have very weak validation hence they decide NOT to offer zero or low insurance! Finally, it is worth pointing out, that Comodo offers high validation, but not at the compromise of speed. You can still obtain SSL extremely quickly.