Jiu Jitsu is for everyone. Jiu Jitsu has less to do with speed, athleticism, or strength and the most to do with your mindset and how well you learn. Jiu Jitsu is a science and art. You don't have to be a super athlete to be able to defend yourself. Jiu Jitsu allows a smaller person to be able to control or escape a much larger opponent not through athletics, but through body positioning and technique.
Jiu Jitsu is endless. An endless, humble, "student mentality" is required. Ego will make you believe you know more than you actually do. If you believe you already know, you cannot learn. This is why children are easy to teach, they are an open vestile. A sponge ready to absorb. Somewhere along our lives we start believing that we know things. Constantly being open to learn and understanding the humble thought that you know very little, about a subject is essential to grow throughout life. Always be a student in life in order to never stop learning and growing. Jiu Jitsu and life. Solve the endless puzzle. Let's improve.
Consistency
Self Discipline
Self Confidence
Do something long enough and eventually you will get good at it. The more you train, the more you understand, the better you become in the most efficient manner. Much like with anything, the more consistently you put your time and energy into something you want to improve; relationships, personal flaws, jiu jitsu - the better you become. Its obvious, but difficult to fulfill for most.
Self discipline must be learned to achieve the highest level in anything. Emotions are inconsistent. A martial artist disciplines those emotions and understands laziness, and other emotions pass. Some days you won't "feel" like training, working, dieting, and exercising, but pushing past those feelings are the days you need the most.
Learning or working at anything consistently builds confidence. Confidence can lead to an inflated ego. Learning a valuable skill like, how to defend yourself builds self confidence. Self confidence is controlled confidence. A martial artist must control themselves mentally and physically not letting their ego deceive them but being confident and self assured enough to not be fearful.
Control
Controlling an opponent starts within you. You must control your own mind and body before you can control an opponent's. Control your mind by adding techniques, thereby increasing self confidence. In developing self confidence, you gain more control of your fear, anger, and panic...allowing you to keep your mind clear and perform techniques physically, thereby controlling your opponent physically. On the other end, ego control must be learned as well. Your ego will stop you from being humble and continuing to learn.
Mental Toughness
Belief is very powerful. Belief in one's self is even stronger. Getting through tough and uncomfortable things is good for us and makes us stronger. By getting through such tough things we build a foundation of beliefs that we can do anything because we have gone through worse before. Pushing through a tough workout, training session, difficult task, or just pushing yourself towards a goal builds a steel mind. A steel mind that keeps trying and doesn't get punctured.
Focus
Most don't realize there is a proper way to learn. When communicating information you are either sending or receiving information. Sending information can be done through physical actions or speaking. Receiving is done auditorily with your ears, visually through sight, or kinetic through doing and feeling. One, cannot receive and send at the same time for optimal learning. Observe and absorb all you can then put the technique into action physically. Put aside what you think you know and the need to let others know what you think you know, and fully absorb. In time, after years of staying quiet and absorbing all you can, others will begin to ask you to speak so they can absorb what you've learned.