The second sentence: no accumulation, no miles.

The third sentence: you can't eat a big fat man in one bite.

The fourth sentence: many a mickle makes a mickle, and dripping water wears away the stone.

It means:

You can't rush for success in everything, especially in your studies. More need to lay a solid foundation, step by step, this is a long-term accumulation, and it needs constant review to get the true meaning of learning!