If you're not failing every now and again, It's a sign you're not doing anything very innovative.
If you don't get what you want, it's a sign either that you did not seriously want it, or that you tried to bargain over the price.
There is no surer sign of decay in a country than to see the rites of religion held in contempt.
I take a very practical view of raising children. I put a sign in each of their rooms: 'Checkout Time is 18 years.'
Honest disagreement is often a good sign of progress.
The true sign of intelligence is not knowledge but imagination.