Some students who have been practicing for a long time feel that they have practiced long enough. They start to forget about what Aikido is. That's not the right attitude. A good word for that is too 'casual'. When a student has been practicing 10 or 15 years, he sometimes forgets about this line and develops a kind of complacency where he is doing the same thing over and over again without thinking about what he is doing.
People easily get into a rut.
That leads to another question, Sensei. There are things you do inside a dojo and things you do outside a dojo. First of all there are the minimum requirements for the test, having practiced the required hours and knowing the required techniques. However, if possible, a person who will test should have more than that. He should be able to do these techniques with a little bit of room in his mind, to do the techniques and be 'comfortable'.