You can't run a business or anything else on a theory.
Performance stands out like a ton of diamonds. Nonperformance can always be explained away.
What you manage in business is people
We must not be hampered by yesterday's myths in concentrating on today's needs.
Facts from paper are not the same as facts from people. The reliability of the people giving you the facts is as important as the facts themselves.
Business is many things, the least of which is the balance sheet. It is a fluid, ever changing, living thing, sometimes building to great peaks, sometimes falling to crumbled lumps.