In ever single professional development course I have taken, one of the key themes that we are taught in training and mentoring is the establishment of training objectives and measurable goals.
When I am assigned a new Airman, I am required to sit them down and specifically state my expectations. I have been trained to make the expectations easily measurable, and not subjective.
When I develop training plans, I have to write a specific goal, and then define a measurable evaluation. Before conducting any training, I tell my trainee's exactly what I expect them to be able to accomplish upon completion of the training.
It's my responsibility to break down the task, and to go over each step. I am to assume nothing, and develop the tasks so that someone with zero experience will be able to accomplish the task upon completion of the training.
If upon evaluation, my trainee can not perform the task to the measurable objective then I immediately schedule remedial training.
I do not give up or make excuses.
I am continually trying to improve. If someone doesn't get something, I assume that it's because I haven't explained it clearly.
If my Airman were not to get trained properly, my bosses and my commander would hold me responsible.
Like Shez, at Homeschooled Twins, says: If my child doesn't understand, it's my fault, not hers.