A fill is not always needed. Within the void you will find levels of imbalance that are rebalanced before price moves through the entire void and that's enough to stop price. Refining those levels within the void can be tricky but certainly something that can be done consistently enough to make a profit over the long term.
The reason I bring this up is because there is a false notion that all voids/gaps fill which they don't and this can cause traders who are learning to assume this is the case and thus trade accordingly to this falsehood. It also promotes poor thinking. Lastly voids are made up of imbalances not inefficiencies. This is very important and once understood makes all the difference to ones trading decisions.
Forgive me for overstepping on your thread but I find the study of price fascinating.
LSP
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