I really look after my brushes.
In the same way that I have a 'thing' about buying quality brushes, I am also almost obsessive about making sure that they are maintained properly.
I recently received a comment from someone who envied my brushes, and declared that they could often not find their brushes - or that they were clogged in dried paint.
On the few occasions where I've forgotten a brush, hidden among all my other bits and pieces, I've had to bin it when I found it. You see, unless you clean and maintain your brushes immediately after finishing each session they are as good as gone.
This is another aspect of my work which requires discipline and organisation. There is nothing I feel like doing less when I've finished a session than standing in front of a sink covered in oil paint, soap and washing-up liquid.
I go through this routine during a day's painting in the studio as well as at the end. So if there's a break - for the model, for lunch etc - I'll always clean those brushes I've used up to that point.
The way I clean is to use ordinary cheap bars of household soap, and washing-up liquid. I ensure that I'm washing in the direction of the bristles. I'm careful about this, and consequently my brushes do not splay, not matter how long I've had them. For this reason I have a well-maintained collection of brushes old and new.
I also use these breaks to change my white spirit, and to clean and reorganise my palette ready for the next session.
For me there's nothing as satisfying as starting or resuming a session with clean brushes, clean white spirit, a clean area for mixing on the palette and clean rags.
Clearly when painting outside in the landscape all day this discipline has to be modified. There I use plenty of white spirit and vast quantities of rag to clean the brushes, and equally frequent changes of white spirit. This all gets carried home at the end of the day, and sorted out for the next session.