Who lent them the money? Did the government of Venezuela have good credit? It's the creditor's fault as much as - or in this case, arguably more than - the debtor's.

The same applies to some business and personal debt: Sometimes good loans go bad; life has risk; sometimes it's obvious ahead of time. Either way, both parties take on the risk and both are responsible for the outcome. When the creditor is significantly more sophisticated/capable than the debtor - as an extreme example, a credit card company extending credit to someone addicted to gambling - I think the creditor is much more responsible. Another example is Wall Street banks extending credit blindly to real estate investment, causing the 2008 recession.

In government finance, it's a very well-known, well-used tactic for wealthy countries or banks to extend credit to other countries that are unlikely to pay it off (due to limited revenue or competence), eventually giving the creditor significant control of the debtor country. The West used to do it effectively and probably intentionally; China has been doing it more recently. The debtor is starved for capital and won't turn it down; eventually they can't pay and another country has their finger on a trigger at all times: they can call in the loan and bankrupt the debtor at will.