User blog comment:Wildoneshelper/Poll on difficulty approach/@comment-24044003-20131031001445/@comment-3225604-20131031134553

I got another point. Accounts can be created infinitely, while you cannot use too many IPs. That's why it's better to include the IP because the person can create several accounts to vote on the same item. Moreover, we cannot view the IP of the accounts, so it is hard to deduce whether these accounts are sockpuppets to each other. The best for me is not to encourage making accounts. If people want to use multiple IPs, they need to have a lot of phone devices and computers, and that will be costly. It is much better to include the IP.