With what I understood here is that you mean when we are debt free we tend to be lazy but in this regard I totally disagree with you because people or societies doesn't borrow unless they are in a critical condition which will warrant them to borrow if not they will not if they have it, we are all in need of one or two things in life, no one want to be poor but when we found ourselves there we try to rise ourselves and by doing that we tend to take risk by borrowing to invest to meet our daily expenses. When I have a enough why should I borrow it doesn't make any sense to me unless I want to make an investment.
Maybe there are some people who, by having debt, will be motivated to work harder so that they can pay off the loans they have and this requires them not to be lazy because they have debts that they have to pay, but there are also types of people who will not borrow if they don't really need it and this really depends on a person's personality.
When you choose to borrow money to make an investment, of course this will be very risky if the investment cannot run smoothly and it is important for you to be able to think about it before actually deciding to take out a loan to invest, because when the investment we carry out is not in accordance with our wishes. Of course, this will cause problems for ourselves.