That's why you do it once a day or a few times a week until it does look like that. They're literally showing you an example of an exercise to practice. The idea is to do your best to do exactly what is shown in the video, then closely examine the practice drawing that you created as a copy of the one in the video & try to notice any & every part that didn't turn out the same or that could be better. The next time that you practice the exercise, be sure to remind yourself of where you need improvement by looking at your last practice of the exercise, & do your best to discern what you need to do in order to make your current exercise practice drawing look more like the ideal example shown in the tutorial. Try to use suggested/"proper" technique for whatever you're doing. Finally, you want to repeat this process multiple times a week, probably once a day for 3-7 days a week until you're genuinely satisfied with the level of mastery you've achieved with the skill.