Ok, it's nice to know when problems don't exist. I'll give you an example of when it can be very nice. Around about January, I pulled a muscle in my neck area. It was a bit painful, very sore. A month goes by, and a second month goes by, through to April or so, and it was still sore. When I slept, I'd have to be careful with the pillow and whatever. One morning in June I woke up, "Ah, not sore!" A couple of days go by, "Ah, not sore! Oh, how nice! How nice it is not to be sore!" Each day after it, for quite a while, I reflected, "Ah, it's lovely!" and now once a week or so I remember how I had a sore neck for about three months and now I don't have it anymore.
So for me to be aware when that problem doesn't exist brings me happiness, brings me joy, makes me more content. But I also temper it with the thought that it can come again, it can come back. Yet, at least it is not here now. So if we actually know a problem doesn't exist, we have some joy at that time that we are free of some Dukkha for now. That's one benefit.
Another benefit when, say, a mental problem doesn't exist, is if we actually see that we are the reason, that we did something which stopped it existing. For example, you go to breakfast and you are at the end of the line. Everyone else is taking food and you are thinking to yourself, "I'd like to have a banana today, they were lovely yesterday." And you get closer to the food table and - somebody just took three bananas. Now, all this aversion comes up, it just goes berserk, "They took three bananas!".
Now what if your thoughts change and go to Compassion/Lovingkindness for that person who is greedy? "If they do that here, what do they do in their normal life? They are not going to have that many friends, etc. etc." So you think in these ways doing some Compassion/ Lovingkindness. Then all of a sudden you see the anger is gone. You stand there and know, the anger doesn't exist anymore. It doesn't exist. Then you reflect, "How did that happen?" And you see how it happened and then you take more joy that you actually used the practice to make the problem not exist. So it's another nice thing to understand, when you actually see that "a problem doesn't exist!"