Insolvency happens when someone or something doesn't have enough money to pay for what they owe. It's like when you go grocery shopping, but when you get to the checkout you don't have enough money to pay for everything that's in your cart. You can't take any of the groceries home with you unless you find the money somewhere else to pay for it. That's the same thing that happens when someone or something becomes insolvent: they don't have enough money to pay their bills, and they need to figure out where else to get money to pay what they owe.