There was a case a few years back when the decision NOT to winch caused the loss of an aircraft. The Polair Twin Squirrel (bought second-hand after the State Gummint refused to replace the BK117 which had a swim - coincidentally by this same pilot) was sent to rescue rock fishermen trapped by big seas up near Wyong. The choice was made to touch a skid on the rocks to let the fishermen climb on board, instead of winching.
Sadly a big wave came along and washed over the nose of the aircraft, obscuring vision. The pilot hesitated until the water receded and he could see properly before lifting off, but by then a second wave washed over, a bit higher, and put the fires out.
Fishermen and Polair crew rescued off the rocks some time later by ground crew. Squirrel rescued by a Kamov from Hevilift, carried away ignominiously upside down.