When you have a ent-boy, what's the need for hurry?

My son has turned 4, but I'm increasingly impatient with him, believing he is too slow in almost everything. However, sometimes I do wonder, what's the hurry?

One morning, it was already 8 o'clock but my son was still fondling a toy car, while I waited for him to brush his teeth before rushing off to the kindergarten.

"Hurry up! You are already late!" I couldn't help raising my voice.