It is one of those conditions which help to cleanse the mind from defilement. Reflect on this and develop it in your practice. You may think that practicing like this involves hounding yourself, but it doesn't really. Actually it's hounding craving and the defilements. If defilements arise within you, you have to do something to remedy them.
Defilements are like a stray cat.
If you give it as much food as it wants it will always be coming around looking for more food, but if you stop feeding it, after a couple of days it'll stop coming around. It's the same with the defilements, they won't come to disturb you, they'll leave your mind in peace. So rather than being afraid of defilement, make the defilements afraid of you. To make the defilements afraid of you, you must see the Dhamma within your minds. It arises with our knowing and understanding in this way.