Why is there a proverb that "spring is sleepy, summer is weak, and winter just sleeps"?

"Sleepy in spring, weak in summer and just sleeping in winter" means:

This is an excuse for lazy people. Satire at lazy people's jokes that people are sleepy in spring and inconvenient to work in summer. When autumn comes, people are easy to get sleepy, but they are still not suitable for work. Winter is coming, which is just a good time to sleep, that is to say, there is no time to adapt to work all year round.

Other folk proverbs are as follows:

1. Winning a battle thousands of miles away-commanding the battle from thousands of miles away. Describe the general's talent, if the commander is determined.

2. The willow gets stabbed and the mulberry bleeds-a metaphor for generations.

3. A strong dragon does not crush a local snake-a metaphor that a capable person can't cope with local evil forces.

4. Look at the food and eat according to the clothes-quantity: measure the body size with a ruler. Cut: cut. Metaphor according to the specific situation.

5. Empty talk-describes talking without practice, or just talking without practice. ?

6. It's not enough to talk without practice-benefits: kindness. Only verbally promised to give others benefits, the actual benefits others can not get.

7. Mantra-originally refers to the Zen language or Buddha name that monks often say. Now refers to those words that are often talked about and have no practical significance.