If you do the job well you can make a good living out of it. If you just want to milk students to fill up your log book, don't expect to get any satisfaction out of it. And don't think that won't be glaringly obvious in a job interview.
Clare Prop, is this partly to do with the weather in Aus though? In the UK I've read on here that PPL instructors typically earn £20 - £25 per hour and can expect realistically to fly 500 hours per year. That equates to £10k - £12.5k per year. With the cost of living in the UK that is barely enough to live on let alone have any kind of life.
I'd love to instruct but just see how it can be viable unless doing you're wealthy enough not to need the money, or doing it part time alongside a better paying job. Unfortunatley job satisfaction does not pay the bills!