You can't be passionate when you feel like it. You have to be passionate about your job, product or cause all the time. There's no off switch on a tiger.
Don't let ups and downs leave you down and out.
I'm a little shot that just kept on shooting.
The longer they keep you waiting, the more they want to deal.
Good commanders look after their troops, and good troops look after their commanders.
Just because an employee does things differently doesn't mean he or she won't do the job right or as well. If you establish expectations of the goal and the standards to follow, then methodology shouldn't be an issue.