Touching is easier than finishing. Under the standard model the probability of touching a level is approximately twice the probability of ending past it, because for every path that finishes beyond the strike there is a mirror path that touches and comes back.
This is the number that matters for anyone who manages positions rather than holding to expiry. A short strike with a 20% chance of expiring in the money has roughly a 40% chance of being tested, and being tested is when the loss, the stress, and the decision to roll actually happen.
Example: XYZ at $50, short the 45-day $45 put with a 22% probability of finishing in the money. The probability of touch is about 44%. Nearly half the time you will watch XYZ trade at $45 before expiration, whatever the final outcome.
Related: probability-itm, tested-side, delta-as-probability, management-at-21-dte