For example, if you set consumeitem to Glowstonedust (3) and you only have one - cancel the action.

Same for tools, if they don't have enough durability.

There is a way around it with "tool: redstone_dust/3" requiring 3 of that item before the section will process.

I do think that it might be more intuitive if the event was cancelled upon not having enough though, will think about it.