What consolidation does
Consolidation replaces several balances with one. The benefit is a single payment and, if the new rate is lower than the weighted average of the old ones, less interest.
It does not reduce the amount owed. Any advertised reduction in the principal is a different process — debt settlement — with materially different consequences.
When it tends to work
The new rate is genuinely lower than the weighted average of what it replaces; the term is not extended so far that total interest rises; fees do not absorb the saving; and the closed accounts are not immediately used again.
When it tends not to work
If spending continues at the same level, consolidation frequently ends with both the consolidation loan and fresh balances on the original accounts. Extending a short balance over many years can also raise total interest even at a lower rate.
Alternatives to consider
A balance transfer promotion can be cheaper for card debt if repaid within the promotional window. Non-profit credit counselling agencies in both the U.S. and Canada arrange debt management programs with creditors. For severe difficulty, formal insolvency advice is regulated and often free at first consultation.