If you think you have a coyote figured out, guess again. Coyotes will produce head scratching in the most profound ways. Coyotes are not unlike humans. They don't like to bust through thick brush. They don't like to hang out in the rain. When they are hungry, they are usually hangry. And they are defensive over their mates and children.
Playing on a coyotes instincts can help a lot with a successful hunt. You can't just throw out a distress sound and think a coyote is going to come running to the dinner bell. It's best to see what they could be eating, how much of that food is in the area and how difficult it is for them to get that food. If they are well fed, the weather is good and they don't have any hardships, sometimes distress calls won't work. Then there is the weather. Just like us when we run to get the bread and milk before a snow storm coyotes think almost the same. When the weather is nasty, it's harder to hunt. Thus the coyote will try to get some grub before mother nature takes a dump.
Then there is breeding season. Breeding for coyotes is tricky as males will mate with multiple females, sometimes crossing into enemy territory. Female submissive howls may work, but sometimes male challenge howls get a better response. And during this time, mommy coyote also has the motherly instinct, so a pup distress can help too. Birthing season is a tough time to hunt. Mothers do not venture away from dens very often, so calling in one from a distance usually will not work. Again, pup distress will work sometimes, but not always. Daddy coyote has left and will probably end up on Maury Povich being told "you might be the father". After mating season is over, mommy coyote usually kicks her donor to the curb and forces him out of the area of the den. The only thing he is worried about is the occasional dinner and not crossing paths with another male coyote.
Then there are the rogue coyotes that follow none of these rules, show up when you don't expect it and act completely different than most coyotes. These are usually yearling coyotes that are uneducated and have not learned how the world works. These usually wind up catching a fast moving pill to cure their stupidity.
The best advice that I can give anyone is to study the area that is being hunted, look at shelter, food and water, ease of travel for the coyote, weather patterns and what time of year it is and then try everything you can. Because a coyote will change the rules as they see fit and there is nothing anyone can do about it.