Too many times I see people on the courts taking lessons, and this hilarious movie scene crosses my mind.
Coaching is extremely useful if your coach knows what they are talking about. You can get real-time feedback on your technique, and get live balls fed to you until you practice away bad habits. Unfortunately, the opposite is also true. If your coach doesn’t know what they’re doing or are teaching you wrong technique, you are ironing into your brain the wrong bad habits, and these become difficult to correct later on. So finding a good coach is very important. But even more important is educating yourself on what constitutes proper technique so you can weed out the endless garbage that gets spewed your way by idiot coaches.
I am a big proponent of getting coaching from Juniors who are highly ranked and play competitively. Often these juniors will teach tennis as a way to earn money and get extra court time. If they are highly ranked and technically sound, they probably get good coaching themselves and will pass along what they have learned. Make sure they are ranked highly though.
A good junior will likely charge much less than a “tennis pro” who has been out of the competitive game for probably a decade or more. The older coaches have missed out on developments as the game of tennis has evolved, and the technology has evolved. It used to be that people used wooden racquets and hit predominantly with closed or neutral stances. They used to use eastern grips and hit the ball with slice or no spin (no topspin!). If you get coaching from an old fart who grew up playing this kind of game, and still teaches the way they learned, you’re never going to win against someone who plays modern tennis.
A lot of coaches are very brainless in how they get you to train. They are basically just standing there with a big basket of balls and feeding them to you like a ball machine. There is a time and place for repetition, but you should always be practicing a certain component of your technique, a certain footwork pattern, or practicing a certain type of shot when you are training. If they aren’t giving you specific instructions as to what to work on during drills, they are probably just pulling a Chubs Peterson and not giving 2 hoots about your development as a player.
Ideally you want them to feed you balls, get you moving, then give you instruction as to what they see you are doing wrong. From there, they should construct a drill to improve the identified flaw, and repeat over and over for all your various shots.
At the end of the day, you should realize that coaches are people too and not everyone knows everything. Sometimes only half of what they say is useful. You can take this useful instruction, but you must also weed out what you know to be incorrect through your own readings and research.
I used to teach back when I was 14 and 15, and some of the other juniors that were teaching were just terrible, teaching the wrong grips and everything. If you are looking for a coach for your kid who is just starting, probably 90% of the coaches out there just do rinky-dink daycare camps where they don’t offer any technical instruction and just have the kids play games for a few hours while their parents are away. They honestly get kids to play ‘tennis baseball’ for a few hours just to pass the time and not have to do any serious instruction. Avoid these daycare camps because you can spend your money much more wisely. You kid won’t learn anything about tennis and will just pick up bad habits. They’d probably develop better habits by taking a dance class, because at least then they would be developing good footwork and coordination. They might not have as much fun at first if they’re getting real lessons, but when they start crushing the other losery kids with their superior technique later on, they’ll thank you for it.