This quote is suggesting that resilience is a necessary trait that everyone should strive towards. It is speaking to the idea of not giving up, no matter how hard the situation. It suggests that you should try to remain positive and smile, even when you are faced with difficult circumstances. This could mean that even if you receive a difficult setback, such as being slapped in the face, you should still find ways to remain positive and smile. This attitude should be present for every hour of the day, suggesting that you should always be ready and willing to face whatever life throws at you.