handle, deal with, dispose of, sell, be in demand, be worldly, be frank, be sensible, be sociable, drainage, sale, demand for, eight
捌 centers on actively managing something so it flows smoothly: handling tasks, dealing with people, disposing of goods, or selling items that are in demand. The idea of drainage and the number eight are less common applications of this same managing/flowing concept.
捌 combines 扌 (hand) with 别, which likely contributes the sound and the idea of separating or dividing. The character suggests using hands to sort, manage, or distribute things.
A hand 扌 beside 别, which looks like a mouth 口 and a knife 刂, suggests using your hands to talk and cut through tasks: handling, dealing with, and disposing of things smoothly.
For ハツ, imagine a manager handling a sudden rush of demand by putting on a hat and getting to work: hat -> ハツ, and the hand 扌 quickly deals with everything.
handling (e.g. knife, reins); control; use; -work (e.g. footwork)
to handle well; to handle deftly
drainage; draining
to sell well; to sell out
to drain; to flow (unobstructed); to run off
market (for goods); outlet
defensive body movement (judo, kendo, etc.)
battling to knock away the hands of one's opponent, in order to achieve an advantageous position
to settle (a matter)
selling
to drain away
to cut; to slit; to cut open