"Remember what God did to Miriam on your way out of Egypt." (Deuteronomy 24:9)
Six Zechirot
Six times the Torah commands us to remember certain events. The six zechirot ("remembrances") are listed after the morning prayers:
The Exodus from Egypt.
The Torah's revelation at Sinai.
The attack of Amalek and the command to destroy him.
The rebellious acts of the Israelites in the desert.
The Sabbath day.
Miriam's punishment for slandering Moses.
The first five are clearly important for us to remember, as they are major events or fundamental principles of faith. Yet the last one, Miriam's punishment for slandering Moses, doesn't seem to fit with the rest of the list. Can we 
Miriam's punishment for slandering Moses doesn't seem to fit with the rest of the list.
consider Miriam's mistake in judgment on par with historical milestones such as the Exodus from Egypt or the revelation of Torah?
In order to appreciate the fundamental lesson of Miriam's punishment, we must understand the essence of her error.
Moses' Prophetic Level
The Torah relates (Numbers 12:1-15) how Miriam spoke against her younger brother Moses for neglecting his wife. Miriam felt that the fact that Moses was a prophet was not an excuse for his behavior: "Is it only to Moses that God speaks? Does He not also speak to us?" Even though they - Miriam and Aaron - were also prophets, they still maintained normal family relations.
God responded to this accusation by appearing suddenly to Miriam and Aaron:
"Listen carefully to My words. If someone among you experiences Divine prophecy, then I make Myself known to him in a vision; I speak to him in a dream. This is not true of My servant Moses.... With him, I speak face to face... so that he sees a true picture of God."
Far worse than her sin of slander, Miriam erred in her evaluation of the nature of Moses' prophecy. Had Moses been just a regular prophet, Miriam would have been correct in her criticism. But, in fact, Moses' prophetic vision was on a higher plane than common prophecy. Moses' vision was not distorted and murky, but crystal clear - he saw through an aspaklaria me'irah. As a result, the Five Books of Moses are on a higher level than the other books of the Bible. No prophet may challenge or contradict Moses' prophecies.
It is for this reason that we are admonished to remember Miriam's punishment for speaking against Moses. By recalling her mistake, we are reminded to appreciate the unique nature of Moses' prophetic vision.
[Adapted from Olat Re'iyah vol. I, p. 334]