whitecosmos:

Protoss

1. While each individual unit is expensive, it isn’t strong.
2. A wide variety of magic units that doesn’t exist, and the Sentry exists
3. Using a Prism, they can explode in either behind their opponent or at their main base
4. They produce High Templars to waste gas
5. Because Shields recover their health really fast, they quickly get hit by an EMP when the battle ends.
6. They use Warp Gates to quickly increase the number of corpses in the battle field

Zerg

1. While each individual unit is weak, it isn’t cheap.
2. With quick mobility they get shaken up by their opponents
3. With larva inject, they quickly make Siege Tanks a commander.
4. They take a lot of expansions so you can get harassed
5. Because they can transition to different unit compositions quickly, they give Terrans the joy of choosing which composition they want to eat.
6. They can use Nydus Worms to blow away your gas. Use it when declaring Bankruptcy

Terran

1. While their fire power is really strong, they also has a lot of health 
2. While they are really strong while holding the ground, they are also really strong while moving
3. While having an incredible prowess in defense,  they also have an incredible ability to harass
4. While having cost efficient units, they can mine very quickly
5. While having strong compositions, just massing one unit is strong.
6. While having a use for every individual unit, swapping and reactors are possible. 
7. While having Planetary Fortress, they have infinite range to summon MULEs
8. While they have a lot of combat units, they also have a wide variety of skills
9. While they’re strong in the early game, their death ball is really strong.
10. While they get a great boost from upgrades, they’re strong even without upgrades

Source: Fomos Community Boards