I'm 54 years old, took a lesson (two actually) for the first time in my life.
I've played as low as a 7.2 before, I'm closer to a 14 right now, so I've never really thought I needed that much work. My biggest issue was my ball striking - I miss a lot of greens, mostly right/short. I hit the ball very high with a ton of spin and wind just eats me up. I've got a good short game so cover for it frequently and do a very good job of managing my misses so that I'm not dropping penalty shots, but it's always something that bugged me. I used to keep full statistics and for about 4 years I would average
maybe 8 GIR. 2017 = 5.3 GIR, 2016 = 6.33 GIR. Almost never in double-digits. Pretty sad considering par 5's are pretty trivial and 4 times you're putting it on a peg so little excuse to miss those as well. So I went in wanting to address my ball striking.
Wow, was my swing jacked up.
First lesson was 4 weeks ago. So, so many changes. My head was swimming. Left foot open, right foot up, shoulders level, hands lower/closer, toe of the club off the ground, right hand strong, face square - all in 45 minutes. I'm also a very cerebral golfer, I always have a ton going through my mind as I set up, so it's overload right now. I went home and watched some Dell Championship and was amazed just how in close to their bodies the pros set up with their hands, hanging down straight from their shoulders. I'm more amazed I never noticed it before and realized just how much I was extending my arms - I was probably at a 30 degree extension which was the litmus of all the other things that crept in.
When I went to check out (Golf Galaxy) the pro rang me up and pointed to the rate sheet and asked "how many lessons you going to get?". Before I could answer 3/$69.99 each, he said "if you go with 10, you only pay for each lesson individually and if you don't complete them no obligation". I glance at the rate sheet and see $39.99. "So you're telling me I can pay 70 bucks today or I can pay 40 bucks today, my choice?" Yep, I'll take 40 thanks. He's a great golf guy but not so much a business guy

I'll take it.
Second lesson was two weeks ago, more of the same but really focusing on getting my arms to hang free and getting the correct stance angle - I had been letting my weight drift back onto my heels on setup which caused a correction mid-swing that resulted in shanks - I was shanking close to 50% of them at times. Still a very busy mind and it's easy to miss one or two details at times. Heck one thing I didn't even notice last night was the pullover I was wearing was a bit tight through the shoulders, constricting my swing. Once I took it off I was instantly striking the ball way better. Note to self, looser clothing.
I missed my chance to schedule lesson #3 today, I booked one for tomorrow. I was at the range last night and once I got everything into the correct routine I was hitting beauties but it's all left - sometimes maybe 10-20 feet left of alignment and dead straight, which I can live with but would like to fix, but others start there and then have some draw to them and go screaming left - those will miss greens and maybe even fairways if not corrected. That's next. Haven't addressed tee shots yet, may just keep grinding out $40 lessons.
If you are spending more than $300 a year golfing, do yourself a favor and go take lessons. I'm stunned just how well and quickly this guy addresses some issues for me and now I get to spend the rest of my days regretting not doing it 30 years ago.