It's a video game. A source of entertainment. It isn't something that you need to set a time commitment for; It's something that you should be able to enjoy in your free time. The only deciding factor on whether or not it was 'worth it' should be whether or not you could have found something else to do in your free time for a reduced cost. You seem to be operating under the assumption that game studios owe it to the consumer to provide thousands of hours of entertainment and that everyone who plays a game for six weeks is causing the MMO industry to settle for mediocrity. This is blatantly fucking stupid.
In reference to MMOs that I haven't quit in less than 6 weeks, off the top of my head:
- EQ (12 years)
- AO (On & off for 2 years)
- DAOC (4 years)
- Rift (~1.5 years, HK was awesome)
- Wildstar (~6 months)
- Final Fantasy XIV (on and off for 2 years)
- WoW - (4 years)
Of course a significant part of that fun is that I play with others and we don't spend our entire time talking about how 'IN THE GOOD OLD DAYS OF EAST COMMONLANDS WE HAD TRUE IMMERSION' and instead, you know, play the game. You should try that and see if it works for you too.