You're probably thinking of [flagged] [dead]. People can keep downvoting a -4 post indefinitely and it won't do anything to hide the post or reduce the poster's

You're probably thinking of [flagged] [dead]. People can keep downvoting a -4 post indefinitely and it won't do anything to hide the post or reduce the poster's karma total. People have to separately flag the post, apart from downvoting, for it to become [flagged] [dead]. It's easy to misinterpret because posts that attract heavy downvoting also tend to attract flagging.