Quality artist materials are expensive, therefore we need to ensure we chose the appropriate materials for the application and look after our tools correctly.
Cleaning and preserving your favorite paint brush will assist in producing a quality painting every time, a worn out frayed brush may not give the desired stroke required, i.e. to create a clean line, a damaged brush can be saved though to create texture.
An artist needs to understand which type of paint brush is suited to the application at hand, different types of brushes are used to create different effects as well as hold certain mediums better than others.
A bristle or sable brush may be the correct brush to use when applying oil paint onto stretched canvas but the same brush may not be the best choice for watercolor on paper, it is really a personal preference and depends on the style of art the artist is trying to create but there are some guidelines worth noting prior to going out and purchasing your paint brushes.
Understanding the basics can save a lot of money and time, it allows the artist to get the desired effect and reduces frustrations, disappointment, wasting materials and damaging ones prized brushes.
Please refer below for several handy links relating to the above:
http://www.winsornewton.com/na/discover/tips-and-techniques/choosing-your-brush-us
http://www.art-is-fun.com/paintbrushes-for-watercolors/
http://www.winsornewton.com/na/discover/tips-and-techniques/water-colour-surfaces-a-go-to-glossary