Cleaning u’re brushes is a necessity as everytime u use them they pick-up makeup as well as all the natural oil on u’re face.
Soak u’re brushes in a shallow pan with normal tap water and add to it 2 drops of disinfectant and a mild shower gel or baby shampoo.. lay them flat so u don’t ruin the shape of the bristles. Swirl them around every 5 mins and lay them flat on a towel to air-dry.
Sponges should be soaked for a longer time. (disposable sponges are better) so u just toss them out!
I religiously clean my brushes after every use it's become a habit
Tip: keep ur brush cleanser (I use MAC) in a travel size spray bottle which u can get from any drug store and just spray and clean ur brushes after every use
I do that very often too. I use makeup remover for foundation brush since i use it so much and soak my brushes in water with cleansing lotion or gel or whatever I am using at that time. Works wonder.