Compare several signal lists and see what appears in all of them: the same time, asset and direction. When independent lists agree, the signal is usually more interesting to analyze than one that appears only once.
Use list confluence when you have more than one source of signals and want to keep only what several of them agree on. It is a simple way to reduce the number of entries and prioritize those with more agreement.
In practice, confluence is great for combining sources you already follow. If three lists point to the same asset, at the same time and in the same direction, that signal deserves more attention than one that appears only once. Still, the result is a filter, not a guarantee: the next step is always to test the final list in the backtest and watch its performance for a few days.