In today's, In "stingy" times, only the price usually counts, thereby saves, who cares about quality, often get into trouble.
A brush should take paint well, keep drip-free and dispense evenly. Sounds easy, but some painting tools are very stubborn. The multi-part brush set from the rummage table for a few euros cannot work miracles. And when the bristles are already pointing in all directions (see right), then the painter's hair can only stand on end.
A Chinese bristle brush is tested by “flaking” it with your thumb. First, the shorter bristles stand up again, they must not be in the majority. Another quality feature is the brush strength. A sparsely equipped brush requires frequent dipping and has an uneven stroke. The texture of the stem also plays a role, so untreated wood is less slippery. So always try it out, whether the brush lies well in the hand.