well most of the time its about asset stripping and loading up a company with expensive debt and selling it before the chickens come home to roost as a recent number of company collapses in the uk proves)

Or its about forcing companys to do trendy things - bad for the long term by selling off core assets on the cheap BT selling O2 is a classic example.

In theory leveraged buyouts are all about what you describe: getting rid of incompetent management, shedding non-core businesses, and restructuring the company to be more efficient. In practice, LBOs tend to leave companies weaker than before, since people like Carl Icahn strip cash reserves and load the company up on debt instead. This means that the company is running much closer to its financial red-line than before, and so when an unforeseen contingency occurs (like a year of bad sales, or an economic recession) the company is forced into bankruptcy with ruinous costs for its remaining shareholders, managers, and line workers.