It's disheartening to come across potential employees during interview that have been let go from some of the bigger 'names' in the industry - they're amazed that such a respectable company, who put them through such a gruelling selection process would ever do such a thing.

They learn that lesson quickly, and I do think that many companies trade on the starry-eyed notion some inexperienced engineers have - and that's bad.

As you rightly say, at the end of the day your employment is essentially a transactional experience and you need to keep your options open.