Takchess asked me the following:
Invasion. Is this basically your opponent can't effectively stop your attack? ie: bad defensive position.
At first I thought that the ultimate goal to strive for in the middlegame was piece activity. Later I found out that the ultimate goal of piece activity is invasion. The point of invasion is that it hampers the communication of the pieces of the opponent. It divides the board in parts. Every piece with a higher value than the invading piece is hindered by the invader. These pieces cannot move freely in their own territory. Hence there is trouble to defend.
How do you find the invasion square? The invasion square is where you can have the upper hand. Where your own pieces converge and where the defenders can be outnumbered, or chased/traded/decoyed away.
Why is invasion so often a motif in complex positions? Because most other motifs are usually simple to see. Common tactical basic motifs like a discovered attack or a knightfork etc. are easy to spot since they have clearly visible targets in the form of pieces. But an invasion is against a square. Whether there is a piece or pawn on the square or not. The motifs that are easy to spot you will not find in complicated positions. As the central motif, I mean. You will find them to be the central motif in simple positions.
What has overloading to do with it? The invasion square is hard to spot, but it needs defence from pieces. If a defending piece has another piece to defend too, besides the invasion square, it can easy become overworked while that is hard to spot.
Imbalanced Material Conclusion
8 hours ago