I did not say most PE companies fail, just that 'often' aka one pattern for PE is to over leverage as a risk mitigation strategy. Every dollar they pull out is a dollar they keep independent of how much the company tanks.

As to over leveraged, the most attractive targets for PE is when the companies assets are worth more than their stock. That's the opposite of being highly leveraged. Remember, profit and assets are two very different things and a company can lose money while still having a lot of capital.