I understand that, say for example you invested $1,000, that could eventually be worth £0 but could you ever end up owing money? - say the coin crashed and the company running it had debts for example.
Yes you might end up losing all the money that you have invested if the ICO failed, some companies who have an ICO if they dont hit the cap for the ICO they will just abandon the project, while some other ICO are built to scam people, while there are still some successful companies who manage well their project, finding the right company to invest in ICO is going to be hard.