There is a big hype around achievements. Blizzards implemented several features like zone- and guild-wide achievement announcement to make sure you cannot miss their existence.
Let's analyze achievements both from RL-wise and RP-wise:
From the RP point of view we are fighters on the side of the people of Azeroth, fighting the Burning Legion and Arthas's scourge. To succeed we need to prepare both in gear and skill to face the forces of evil. From this point running around the world to get every gray area out of Ashenvale or giving /hug to corpses is pretty pointless and stupid.
From the point of the RL, you are playing a game either to have an escape or to participate in a simulated world to hone your real world skills:
- mathematics in theoricrafting
- quick reactions in complicated bossfights of PvP
- leadership in leading a guild or raid
- social skills in solving drama situations
I'm wrong. The achievement system simulates something really important from the real life: can you resist the stupid "I have better car than my neighbor" fever? Can you resist wasting your resources in something completely pointless just to look better in the public eye?
To reach any goal, both in WoW and RL you must assign your resources to that goal:
- If you want to be rich in either worlds, you must gather seed money and invest it into some business that will only take money in the initial period.
- If you want to be an athlete either in the Arena or your county's swimming team you must spend your time on practicing and spend your money to buy you more time.
- If you want to beat a hard boss or find a cure for a disease, you must spend your money buying gear for the fight and spend your time doing your homework.
I've written it already and write it again: resist the temptation of wasting your time and money into something useless, but visible and of prestige! Invest it into something useful! Achievement system is a great tool to practice it in this simulated world. Just ignore it, don't mind having less than anyone you know. Every time you see an announcement "XX unlocked achievement YY", tell yourself: "these points are useless, give me nothing. I go for my goal and not for the public eye"