ME was really a punishment from Microsoft. They had warned people not to use the DOS family anymore yet people just kept using Windows 98. So MS decided to poison the well, so to speak, in regards to their DOS line and to make some last minute money from the people that refused to listen to them. They had given many years of warning to migrate everything to Windows 2000 or later but people just ignored them. Microsoft waited to do it until NT 4 had been replaced because Windows 2000 felt so much more modern. They didn't want to make the experience poor for anyone.
But Windows 2000 adoption was terrible. So they brought out ME to show people why they needed to switch, and fast. Then they brought out XP with lots of extra polish and charm that 2000 lacked. The play worked and people moved over completely within a year or two. It was executed perfectly on Microsoft's part. And anyone that listened to Microsoft didn't get hurt because they gave so much warning and were so public about it.