I believe once they are commissioned they are given a number (eg current ones are GOES-13, GOES-14, GOES-15). They are also given a designation as GOES-EAST or

I believe once they are commissioned they are given a number (eg current ones are GOES-13, GOES-14, GOES-15). They are also given a designation as GOES-EAST or GOES-WEST depending on where they are being used. So GOES-13 was GOES-EAST until it had an anomaly and GOES-14 was moved out of a storage orbit and designated GOES-EAST. It returned to storage once they fixed the issue with GOES-13. The R is just a sequence number for launching; S and T are slated next. If there is a failure before commissioning, it won't receive a numerical designation. So the GOES-R name was just a happy accident I guess.