You're owning, but your team is losing. Here's why and how you can overcome it.

It's usually the same situation. You picked (or randomed) a playmaker hero that starts in mid, and then you created space. Towards endgame, one team's carries announce that their farming is done and commenced the endless teamfight until one team's throne has given way and you sit back and enjoy/rue the scoreboard. No complaints for the times that you do win, so today we're going to discuss about the times when you lose, and maybe you can find ways to win even faster/get out of the situation.

The ideal scenario

At level 6, or with the 8th minute rune (whichever is more advantageous, depending on the hero/farm), you, as the playmaker, decides to gank the safelane that has been pressured so far. Hasted/DD'ed/Invi'd, you get into position, initiate and get the kill. You repeat the same for the other laning partner, and start clearing the lane. Sometime between that, the Nature's Prophet teleports from his farming in the jungle, and with four man in the lane you start pushing and take the T1 tower. Before they can respawn and have the rest of the non-TP-carrying team get here, you've already downed the tower and given your carry the last hit on the tower. Repeat the above 5 more times, and you'd be pressuring their T3 and with an advantageous fight, cleared enough space to Rosh comfortably. With the Aegis and a 15k advantage at 25 minutes, you push high ground and eke out a timid GG from the other team.

Easy, right? Doesn't matter what heroes were picked, really, and you could easily replace Nature's Prophet with Enigma/Chen/Enchantress and the results will still be the same-ish.

That's a little too rosy

Of course it is. It assumes that the opponents never bought an item past GG Iron Branches and Tango, never did anything beyond last hitting and stayed in his lane until the last tower fell and he had to play from behind the T3.

I'm going to start off by saying that Dota 2 is a game about teamwork. The simplest question I'm going to ask that you reflect about yourself is that do you play better in a party or do you play better solo queue. For me, I find that I play better with my own friends, simply because we know how to work together (or I'd spam ">Well Played!" when they die) and we know how to work together.

Secondly, Dota is a game with objectives. There is is only 2 sides, and the losing side is the one with their Ancient blown up. Simple. There is only ONE single thing that needs to be done to win. Blow up enemy Ancient. Getting there is another matter, but blowing up the Ancient is the way to go.

Thirdly, all advantages are relative. It is pointless to have 100 kills as solo mid but having a shitty farming carry and a team that can't breach high ground because they split push too well and their carry has better lategame presence. Always be aware of your team's power window and don't drag games beyond that. Don't try to start the festivities before you're ready either. Every hero has a counter, and every kill is supposed to net you some gold advantage

Consider the ideal scenario in light of these three factors and I believe that you can actually figure out how, and why, getting a 30 minute GG is not impossible, even when both teams have players with similar mechanics and skills.

How does this relate to situation in the first place?!

So now that you see the ideal scenario that could take place, apply it to your situation:

Teamwork & communication is the foundation to success. 

If the jungler is unaware of the imminent gank, or the team is impatient and didn't wait for the right initiation, the kill wouldn't have happened. If the team didn't stick around and tried for some pressure on the tower, they probably wouldn't be able to take it down either.

Ganking is important

Even a gank that resulted in zero kills is to your advantage, as the opponent will back off until the playmaker re-appeared somewhere else in the map. A solo mid that stays in lane is not fully utilizing the advantages of the farm and the XP from going mid.

Pushing is also important

I've seen a solo mid get beyond godlike in midgame, then losing the game as the opponents pushed more effectively and raxed. I've also played as that idiot solo mid, and played against such idiot solo mids. Whenever you have the advantage, always take the tower after a successful gank.

Maximizing that momentum is important

Understand that relative gold advantage is better than absolute gold advantage. A kill will net you approximately 250-750 immediate gold advantage, and scaling it to the farming space gain/loss you'd be having close to 1k gold advantage per kill. That kill doesn't mean you are now allowed to go back to the jungle and farm, but you need to take that momentum and bring it to the other lanes. Force the opponents to play defensively and your team can now do more. Constantly apply pressure and starve them of farm until they can't walk out of base without dying.

Utilizing that space is important

Your team must be able to capitalize on the space created and start creating advantages. Taking down a tower gives your team a 1.2k to 1.5k gold advantage. Multiply that by 6 and your team now resides in an unassailable position. The important thing is not getting the gold for your core heroes but for your supports. Some items will let them live longer and not get melted when they are focused down.

There are, of course, other little things that can help you along the way, but these general principals outline what is important for your team to win your game of Dota

Halp, they read your guide and they are doing this to me. What do now?

Firstly, don't panic. Now, onto some more practical advise:

1. Teamwork. Try to help each other out. Push together, gank together, and help out players in need.
2. Counterganks. TP in and help FFS.
3. Counterpush. Never give up free towers.
4. Don't go solo. There could be more people in the fog than you realize. Always assume that the hero capable of going invi is invisible and there pushing.
5. Map awareness. Look at your minimap and be aware of the relative positioning of your team and the opponents.