This is not to say that you should never buy gear. Having equipment that is reasonably current while leveling allows you to kill enemies faster, and die less often in the process. Faster leveling = sooner to higher levels (where the real money is to be made). Likewise, death = loss of time. And, as we all know, "Time is money, friend!" So, players should not hesitate to make well-considered equipment acquisitions during their leveling up, but only if they represent a substantial improvement over their existing equipment and if the price is right. Try to find good deals. It should go without saying that you should never purchase any equipment from vendors; always use the Auction House. Look several levels above and below your own for bargains. Don't buy items that you won't hold onto for at least 4-5 levels. And don't always use the buyout option at the AH. Some of the best deals come from bidding and being patient - it'll be two days at the most. Of course, if you play too hard you may have surpassed that weapon by the time you win it. In which case, you may want to auction it again. If you know there's an item that would be great for you, say, five levels from now, keep your eye out for it and bid on it, several times if need be. When you get it, stuff it away for later. That's why you have a bank alt.
Formerly, when you visited a new zone, you would be very careful, tiptoeing around, cause everything was higher level than you. But as you dinged (leveled up), you would get more powerful relative to the locals. So you would feel more confident and capable. Dinging came to represent more HP, more Mana, better hit ratio, more crits, more talent points. you felt REALLY good when you dinged, like you had accomplished something. Almost tangible. You would think "now I can go back and take that mob/group that ganked me". And then when you had done all the quests, you would move to another zone and do it again. Fun!