We may look first to the first tribe mentioned in the list of Revelation, which is the Tribe of Judah. this is interesting because Reuben should have been first, but we will remember from Hebrew history that Reuben lost his position of first because of his gross immortality and thus it was given to Judah.
Genesis 49:8-10:
(8) Judah, thou art he whom thy brethren shall praise: thy hand shall be in the neck of thine enemies; thy father's children shall bow down before thee.
(9) Judah is a lion's whelp: from the prey, my son, thou art gone up: he stooped down, he couched as a lion, and as an old lion; who shall rouse him up?
(10) The sceptre shall not depart from Judah, nor a lawgiver from between his feet, until Shiloh come; and unto him shall the gathering of the people be.
Genesis 49:3-4:
(3) Reuben, thou art my firstborn, my might, and the beginning of my strength, the excellency of dignity, and the excellency of power:
(4) Unstable as water, thou shalt not excel; because thou wentest up to thy father's bed; then defiledst thou it: he went up to my couch.
This shines light onto the subject, showing us the history of the people was being adhered to in this particular list. Other list have other names, and in other orders, and this is because God is communicating something different in those list, but this list deals with the history of the people.
We may accordingly remember that Dan was the first tribe to fall to idolatry after Israel was led into the promised land.
Judges 18:30-31:
(30) And the children of Dan set up the graven image: and Jonathan, the son of Gershom, the son of Manasseh, he and his sons were priests to the tribe of Dan until the day of the captivity of the land.
(31) And they set them up Micah's graven image, which he made, all the time that the house of God was in Shiloh.
Dan is also where the calf was set up when Israel was split as a nation after Solomon.
1 Kings 12:27-30:
(27) If this people go up to do sacrifice in the house of the LORD at Jerusalem, then shall the heart of this people turn again unto their lord, even unto Rehoboam king of Judah, and they shall kill me, and go again to Rehoboam king of Judah.
(28) Whereupon the king took counsel, and made two calves of gold, and said unto them, It is too much for you to go up to Jerusalem: behold thy gods, O Israel, which brought thee up out of the land of Egypt.
(29) And he set the one in Bethel, and the other put he in Dan.
(30) And this thing became a sin: for the people went to worship before the one, even unto Dan.
If you were paying attention to the text above, then you saw that the golden calves were established under the king Jeroboam, who just happens to be of the tribe of Ephraim.
1 Kings 11:26:
(26) And Jeroboam the son of Nebat, an Ephrathite of Zereda, Solomon's servant, whose mother's name was Zeruah, a widow woman, even he lifted up his hand against the king.
This just so happens to be the other tribe which is not included to be a witness for God in the end days.
The list given in Revelation is a list of the 144,000 witnesses in the last days. These tribes lost their witness because of sin.