The identity theft they "protect" is your credit identity. I do not know how well they do it but I have not heard anything bad about them.
What they apparently do not cover are hands on issues with a personal bank account, for example...
If someone physically removes a check from your checkbook, and writes it out to cash, and succeeds, that is different as nothing Lifelock offers protects against that type of identity theft.
Banks are not responsible for this type of problem. Some of them, especially local bacnks where you may know the tellers, may make allowances in such cases of the amounts are not large and you have a good size account in good standing, but banks are not liable for this type of problem.
Most credit cards offer some sort of protection already for identity theft wich often costs a couple of bucks per month per card or per account depending in the company.
If you have twenty such credit cards, all with protection on them, it may save money to use Lifelock instead of paying each card provider. If you are like I am, with a couple of credit cards in good standing and a couple of personal bank accounts, it is less expensive to just pay the monthly add on fee to have the cards protected through the provider.
Now if the junk mail and spam protection is something of value to you, that may be worth the extra few bucks but that is a choice of convenience you can value of your own accord.
For me, the "do not call list", the "remove from mail" and "do not contact" letters I send, do the job just fine for less than the money Lifelock is asking, plus I do not have to provide my confidential information to yet another private company for potential abuse.