Technically balanced matches are a little bit more common in Ranked.
So here's the rough analytical breakdown:
Team Morale (7)
Individual Player Morale (9)
Micro (6)
Macro (3)
Meso (6)
Individual Player Winrate (9)
Connectivity (10)
(In parenthesis I assign an IV or importance value out of 10 of how important that factor is for your chances of winning).
As you can see:
A combination of winrate and connectivity are the most important factors for winning a game.
If you are given a team mate that for whatever reason has a lot of disconnects the enemy team will have a power advantage the moment they disconnect.
Micro is not as important as Morale.
The only thing I am doubting here is the Team Morale Importance Value.
It maybe closer to a 10 than a 7 I gave it.
So if your enemy team has a higher morale than you, and higher connectivity. Nothing can save you unless they're absolutely terrible at Micro. Which teams have good connectivity and good Morale??
6 stacks.
6 stacks are really hard to beat.
To make it harder for a 6 stack the Matchmaking will purposely find Heros with high winrates and Heros that do not give up (high morale) and heros that have good connectivity.
At any moment your own team mates morale can drop.
So what can you do?
At the very start of the match, play conservative. Let your team mates know you are willing to peel, heal or Shield.
If you are DPS peel to save your healers.
If you are strategist heal your tanks.
If you are Tank. Use your shield.
This is how you keep the morale high.