It's actually not about having "earned" it; it's not meant to be a token of having completed the degree, or having been stupendously good at some technical piece of work.
It's meant as a reminder to the obligation you have to society not to cut corners on safety, and that your responsibilities to your employer do not outweigh those you have to Canadians generally.
The Order has been coming up on HN recently because a number of err... unethical practices are being implemented by engineers who are theoretically "just doing their job". There was a request that engineers refuse to do such jobs on ethical grounds, and this was one of the traditions pointed out as doing exactly that.
It's meant as a reminder to the obligation you have to society not to cut corners on safety, and that your responsibilities to your employer do not outweigh those you have to Canadians generally.