Not even the most skilled of Balancers could always stop their Life Energy from completely leaking slight traces.
It was something that required great control over their Life Energy and not all Balancers could reach such a stage where they could freely manipulate their Life Energy without the assistance of a spell or technique of some kind.
Even those high level masters had to sleep and drop their concentration and control at times resulting in traces of their Life Energy leaking enough to leave a trace of them behind that could be tracked or identified.
The spell was aimed towards cleaning up those traces in order to prevent other Balancers to be able to track them but there was something that made the spell counterproductive at times.
Each item usually had some kind of minor traces left from the original person who used it.
