bad debt consolidation

Debt consolidation a good or bad thing?
I missed a part of CNBC’s “The Millionaire Inside” Debt-free program where they mentioned the reasons why debt consolidation is bad. Did anyone catch it or can explain to me why it may be a bad idea. I’m in a program and I’m debating whether I should stay in it.
It may be bad on the short time: you cut your capacity to borrow some money. As long as you don’t pay your consolidation loan, it will be really hard to get some credit.
But on the long-time, you’ll get a real improvement of your credit.
The best thing is to get a consolidation loan from your bank or credit union.
Good luck !