Untapped daily, weekly and monthly levels provide amazing support and resistance levels due to liquidity from trapped traders. For the purposes of this indicator an "untapped" level is defined as a level that price does not close over on the same timeframe. For example and untapped monthly level of support would remain valid (and visible on the chart) until price closed below it on a monthly basis. The longer the timeframe of a level the more weight it carries ie. a monthly level would carry more weight that a weekly and by extension a daily.
While these levels may indicate possible macro reversal points I tend to use them myself more for short term setups and scalp trades. These levels have become a stable addition to my own trading strategy and I believe all traders can benefit by being aware of them on their own charts. Happy trading!