"Not every difficult and dangerous thing is suitable for training, but only that which is conducive to success in achieving the object of our effort"

Epictetus is suggesting that when it comes to training, we need to just concentrate on activities that will assist us reach our objectives. He is saying that not every tough and hazardous thing is suitable for training, and that we should only concentrate on activities that will assist us reach our objectives. He is emphasizing the value of being selective in our training and focusing on activities that will assist us reach our goals. He is also recommending that we need to not squander our time and energy on activities that will not assist us reach our objectives. He is emphasizing the value of being tactical and effective in our training. He is recommending that we ought to focus on activities that will help us reach our goals in the most efficient and efficient way possible. By doing this, we can optimize our possibilities of success.