As a PGA Teaching Professional with over 25 years experience I truly understand the frustration and confusion players experience trying to figure out what is causing their shot problems. Other times most everything is going well with a player's game except for one part such as pitching or chipping. Another situation is the novice player that is getting all kinds of advice from well meaning friends and family members.
All the above mentioned are good candidates for taking a golf lesson. Experiencing the same shot problem over and over such as slicing your driver or hitting your wedges fat or thin can quickly take the enjoyment out to the game. An experienced and qualified PGA teaching professional will quickly identify the cause of your problem and demonstrate to you how to correct it.
Any player who is new to the game will benefit greatly by taking lessons early. They will progress much faster by learning proper fundamentals and the correct way to swing a golf club.
The most common reason people give for not taking lessons is they are afraid the instructor will want to change everything about their swing. An instructor that is truly good at what he does will focus only on the primary cause of your shot problem rather than trying to convert you to a rigid method or swing model. "Less is More" is the advice I always give young inspiring teachers. Keeping it simple means the less you're thinking about during the swing.
Choosing to take a golf lesson whether you're a seasoned player or a novice will clear up your confusion, and answer your questions. As a result you'll be hitting better golf shots and having more fun on the course.