A hammer needs a location, not just a long shadow
Why candle geometry alone does not make a bullish reversal case.
Begin with what the candle records
A hammer has a small real body near the top of its range and a pronounced lower shadow. During that period, sellers drove price down and buyers pushed it back toward the open. That intrabar recovery is evidence, but it is not yet a bullish conclusion.
After a sustained decline or at a level where buyers previously responded, the same shape may deserve attention. In the middle of sideways noise, it may simply record another indecisive interval.
Ask three questions
First: what was price doing before this candle? Second: is the low testing a visible area of support or rejecting an extension? Third: what would the next candle need to do to confirm that buyers retained control?
Writing those answers beside the chart prevents the silhouette from becoming a command. It also gives you an invalidation statement you can review later, without the distortion of hindsight.