The market system rewards me outlandishly for what I do, but that doesn't mean I'm any more deserving of a good life than a teacher or a doctor or someone who fights in Afghanistan.
I do not like debt and do not like to invest in companies that have too much debt, particularly long-term debt. With long-term debt, increases in interest rates can drastically affect company profits and make future cash flows less predictable.
Shares are not mere pieces of paper. They represent part ownership of a business. So, when contemplating an investment, think like a prospective owner.
Cash, though, is to a business as oxygen is to an individual: never thought about when it is present, the only thing in mind when it is absent... When bills come due, only cash is legal tender. Don't leave home without it.