Question

grass is greener on the other side of the fence. give one short example

Answer 1

because people are always comparing their current lifestyle to better ones, longing for improvements.

Answer 2

The grass is always greener on the other side of the fence:

This is a great prover this tells "we must not compare ourself with others", We must be happy with what we are having. The grass is greener on both the sides of the fence. We must not compare about those and maintain our own business/work.

This proverb was by the poetry Publius ovidius naso. Example for the proverb is - If there are 7 greatest people in the world we must not compare between them, we must just try to better than others without comparing others.

We must mind our own business/work. We can see how people are and who are they but comparing is considered wrong according to this proverb.