There is a garden near the place I live. My kids enjoy playing there. The garden service team trims the grass every 3-4 weeks. When the grass is trimmed it looks so lively, lovely and fresh. Kids enjoy and spend more time in the garden. After 2 weeks or so, the grass starts getting taller and turning yellow. This makes the garden unattractive. Also I noticed that the day grass is trimmed and someone throws a cigarette box or any other garbage it looks extremely bad however when the grass is taller and someone throws something, it's hardly visible.
If I consider the grass as human brain and the grass as negative thoughts and cigarette box as stress then I learn a very good moral from this analogy. Let me explain this: When I don't have any negative thoughts and stress I have a beautiful, powerful and fresh mind offering great services to the society, family and all humanity. However if I have negative thoughts (and in turn negative behavior) I start becoming the point of concern for the society, family, friends and colleagues. And when I have too many negative thoughts, I start nourishing roots of stress even if I don't know about it, just like the cigarette box not visible when grass is tall. Hence it is recommended to 'trim the grass' quite often. In my analogy, trimming the grass means to throw away unnecessary thoughts and clean the mind from such garbage. When I have a clean mind (like trimmed grass), I can easily identify the roots of stress (cigarette box in trimmed grass) and easily handle the situation with my analytical skills eventually making my life more beautiful.