It's been a while since I've spent a good half hour or more at the sink scrubbing piles of wide brushes the way you learn to do in the theater, television and movie scene-painting world, spending mindless yet meticulous energy making sure every last one has every last drop of paint washed from the bristles and in the absence of a proper brush rack, that they're carefully folded in clean rags and laid flat to dry.
It has always reminded me of a rider exhausted at the end of a long day of travel feeding, watering and currying her horse before eating her own dinner. A dramatic comparison perhaps, but it often drifts through my mind as I stand there, vigorously scrubbing and scrubbing again with a wire brush and Murphy's Oil soap (good for the bristles).
It's worth it - your next day's work depends on those tools. It's hard to explain the importance of it to someone new to the work. But the alternative - stiff, dirty brushes - is painful. Expensive house painting or two dollar Chinese bristle jobs, I wash all my brushes myself whether I used them or lent them out. And hope the good habits catch on.