There’s the reason why some players used to call the game World of Roguecraft. Rogue was one of the most popular classes in classic WoW and there’s a good reason for it. During vanilla, Rogues topped DPS meters in raids and dungeons, but their main strength was world PvP. Rogues could stealth through enemies avoiding unwanted engagements with the opposing faction. Additionally, a huge variety of crowd control abilities and high burst damage made them the worst nightmare for the cloth-wearing classes. However, Rogues were in a bit of disadvantage regarding end-game gearing since most of their gear pieces were useful to other in-game classes as well.
As you level, you will buy new ranks of spells. If you splurge out on an item upgrade, you will not have enough gold readily available to upgrade to the latest ranks of spells: placing you behind. Moreover, you can buy gear upgrades from the Auction House (AH) or vendors. Furthermore, you may have large investments that need to be paid for professors. You will need to purchase reagents and items such as leather, bolts of cloth, alchemy supplies – unless you have a charitable friend or another high-level alt.