The ledge sweet spot of a ledge is the furthest point from the edge of a platform that a character is still able to grab the ledge in Super Smash Flash 2. This is normally in reference to a recovery such as an up special move, but can be referred to any special move that can act as an recovery. The distance and ledge sweet spot varies from character and specials alike. An example would be Bomberman would be unable to grab the ledge from far away due to his recovery gaining mostly vertical distance and little horizontal distance. Mario is able to grab the ledge from far due to his various recover options. When talking about specials; when Meta Knight tries to use Dimensional Cape to grab the ledge. Most of the time he will not grab the ledge and fall to his death showing that dimensional cape has a small ledge sweet spot.
Certain recoveries are able to auto-sweet spot the ledge. Donkey Kong's Spinning Kong is able to cancel the move and grab the ledge in the moves early frames. However, certain recoveries need to be angled to auto-sweet spot the ledge. Fire Fox can auto-sweet spot the ledge when Fox is up above the ledge aiming down at it then when he is aiming up to grab the ledge from below. They're certain specials that cannot auto-sweet spot the ledge even in the moves early frames. Wario's Corkscrew is unable to auto-sweet spot the ledge which can leave him vulnerable to an edge guarder.
Players try to sweet spot the ledge when recovering to avoid certain edgeguarding tactics and making guard breaking much easier. Sweet spotting avoids most ground attacks and certain aerials by recovering to low to be hit and if they're hit it makes ledge teching much easier. However, trying to sweet spot the ledge makes players vulnerable to edge hogging.