Long term commitment to mastery requires sacrifice and devotion. You have to sacrifice time, money, and energy. You need to make choices about how you will spend your weekends and your evenings after work. You need to find the time in your daily life to practice things. You need to be willing to accept and expect criticism, constantly adjust your goals to be just outside of your reach, and understand that you will meet with failure on the road more often then you will meet with success.
I totally agree. And because there are no competitions, and less emphasis on rank, the choice to continue training is internally driven. More so than in other MA's, I think. Furthermore, because of the nature of Aikido (balance-blending-centering as opposed to muscle) even though there are seasons in life when training is too costly, it's never too late to return.
Aikido hard? Well, yeah.
So is learning a new language, or earning a Bachelors degree.