In accounting terms, an "investment", at the time you make it, does not change your profitability. This is because you are assumed to have received in return an asset of equal value. For example, the purchase of equipment results in a decrease of your cash balance, but an increase in your fixed assets of the same amount. An "expense", on the other hand, does reduce your profitability. So profits are not a sign of a lack of investment, but of revenue that exceeds your expenses, which seems pretty desirable to me.

Accounting: Assets = Liabilities + Capital. This deals with the Balance Sheet. Expenses/Revenues are reported on the Income Statement. Two completely different things. An income statement basically explains how well you're using the items on your balance sheet.