There are different types of manipulations. There are ones that some exchanges or the trading platform officials will be the ones that will be manipulating. But there are also ones that not the exchange that will be manipulating. The exchange officials does not need to be the one manipulating as it can be wash trading and not insider trading.
These different types of manipulations are driven solely to make profit. And not just any profit but massive profit. And these profits are made in my estimation, the wrong way. The wrong way because honest traders are affected. While the manipulators are making profits the honest guys will be counting their losses.