I had lots of issues with other plugins that added an extra field regular commenters wouldn't see. The idea was that spammers accessing comments through a back door would fill in that field and immediately be identified as spammers. But all those caused issues for my real audience who wanted to comment. This plugin solved that by requiring legit commenters to identify themselves (easily) as legitimate. Sure, spammers who just troll sites and manually comment can get through, but that's the problem with spammers, isn't it? There's no single way to block them all.