From His Holiness the Dalai Lama:
Saying that one should be patient and withstand trouble doesn’t mean one should be defeated and overcome. The whole purpose of engaging in the practice of patience is to become stronger in mind, stronger in heart. And you also want to remain calm. If you lose patience and your brain becomes confused with emotion, you will lose the power to analyze and figure out how to overcome the negative force that is opposing you
The term ninja translates as patient person, not assassin or night stalker. The word and the practice are about engaging fully in life, riding the moment, and waiting for the perfect time. It is about knowing that 'good things come to those who wait' and that 'the early bird gets the worm'. With practice, you can learn to tell the difference.
By taking up a physical practice, we are able to see our emotional brain at work. We can see it get stuck, frustrated, and angry. We can also see it prevail. Ultimately, we practice self defense to learn to make our lives brighter, happier, and safer. To do that we need to discern truth clearly.
I believe it is critical to have a practice venue where we can experiment with the success and failure of engaging with truth. Otherwise it's our friends and families who have to practice patience while we try to figure it out.
PS: Sometimes when we talk about patience, we think about this moment, this stress, and this other person who is stressing us out. But the truth is, patience and stress both come from within. No one does anything that makes us have to be patient. Our reaction to others triggers the need to exercise patience. Our desire to achieve a goal causes us to exert patience as perseverance to overcome the obstacles on the path.
In martial arts, sometimes you'll have a frustrating training partner (or more accurately, sometimes you will be frustrated by your experience of your training partner). Attending class every week, twice a week for over 200 weeks takes patience. Keitoshi and I have been steadily training 2x week for over 650 weeks and look what we've accomplished. Patience is the number 1 key to success. It's more important than athletic skill, more important than youth or maturity, more important than liking ninja stuff. Like the tortoise, patience wins the race if what you are striving for is to happier, more capable, and safer.