Jobs has probably made as many smart moves as he has dumb ones, so there's no reason you have to take this definition at face value. His word isn't - yet - gospel. And I have a lot of trouble with the idea that - at any level - reasons ever stop mattering.
I am passionate about the idea of accountability, and holding people to it. But what bugs me about Jobs' definition is that it seems a very good way to shut people up. At any level in an organization, there may be a very good reason why something can't get done - or why it can't get done in the way specified. Understanding those reasons is mission critical. If there's a kink in the system, it may be causing lots of problems, not just one. The VP concerned may not have the authority to fix it. It is possible, even among the super brainy execs at Apple, that not everyone knows how to fix it. Being told that offering up 'excuses' like this makes you a janitor isn't a great way to encourage frankness.
The Danger of Silence
Research into organizational silence indicates that the vast majority of employees (roughly 85%) confront issues at work that they dare not raise: issues of under-performance, dishonesty, inefficiency, poor management. Why can't they be discussed? Because employees feel they will be punished or humiliated when drawing attention to them. But leaders absolutely need to know these things and depend on those around them to be open and honest about them. Creating conditions in which identifying problems is viewed as pathetic is one way to ensure no one tells you the truth.
But who, I wonder, would dare say so to Steve Jobs?