For me the problem is the limitations that were unnecessary.
- You can't modify UI to the fullest (minimap, portrait)
- Empty UI black edges with no 3D render support.
- 8 MB Map Size Limit.
- Bad tile-sets. (Blizzard IS lazy)
- lacking terrain tools (Blizzard Got Lazy)
- No mouse support, keyboard support events.
- Texture size limit - 512 x 512.
- Storyline, ideas, concept and plot is CnP from other games.
- 12 unit selection limit.
- LOTS of things including the game-play of races.
- Unrealism. (Ex: when you resurrect a night elf archer corpse using necromancer it resurrects a skeleton with a sword. Wtf?)
- Same icons for different race units. (Bandits use the same skill icon - Shadowmeld as the Night Elves.)
- Inventory limitations, only 6 slots maximum.
- Low quality models. (Compare these low quality models in retail with Warcraft 3 Alpha RPS- *facepalm)
- In-completed model textures aka rushed. (Blizzard got lazy.)
- Same model for different units with only value colors changed. (Blizzard got lazy.)
- Lots of scrapped great ideas and content from Warcraft 3 Alpha that didn't make into the retail game. (Bad design)
- No direct .MID (Midi) music support. (Blizzard got lazy.) (It is possible to have midi music, but it has no direct support in Sound Editor)
- No direct support for in-game .TGA textures. (Blizzard got lazy.)
- lots of more...
The final product of Warcraft 3 is a dissapointment when you research into it. The only thing that keeps me playing is the easy modding and an advanced world editor. The conclusion is that after many alphas and betas, warcraft 3 is a rushed product with great vision behind it.