Howdy, I don't feel this website is the most active in terms of DIY speakers, but I feel my opinions may be of more value here than other sites. This will probably be quite scatter brained and I'm going to be as open as I can be maybe touching on some deeper personal issues in the end.
I got into DIY speakers a long time ago, starting with PA speakers. I transitioned into home stuff a few years ago, mostly sparked by the things I've learned here at ASR and the fact that I started to get older and not like the loudness as much (I can probably fix this with some good custom molded earplugs). I've made some kits and eventually tried my hand at my own designs. I thought I'd share some of my frustrations in hopes that more experienced folk may confirm or offer counter arguments. This is largely stemming from what I'd consider recent failures.
1. Celebrities - Boy this hobby has a lot of celebrities in it, and while at first I listened and absorbed their information, the further along I get the more I realize many
designers are simply propped up by users with little reference as to what good sound is and not so much that their designs perform well. I see A LOT of popular designers utilizing what
I'd consider very dated approaches to design delivering sub par performance. I've had to take a hard stance and only consider designs that have extensive and trustworthy measurement suites.
I'd consider this design one of dated design principles and a poorly assessed speaker.
Home > Floorstanding Speakers > The Pit Vipers
sites.google.com
And this is what I feel is a well done speaker with what is really the minimum amount of data.
Design description and goals: Bigger Brother to the VBS-6.2 this is another design that delivers a very high level of bang for your buck. A 10" 2-way with a horn loaded compression driver that does not sacrifice sound quality in its ability to deliver high output for very reasonable costs. Ideally
www.mtg-designs.com
2. Everyone wants to sell what they think is best - Go ask for driver recommendations at DIYaudio.com and you'll likely get a mess of recommendations that are nearly impossible to gauge. How does one know who is a reliable source of information there? When requesting data on things, I find many are still neigh on militant towards communities like ASR. It feels like much of the DIY community lives in it's own bubble.
3. The difficulty of making a GOOD speaker is vastly underestimated - I'm very guilty of this. I was under the impression that with time I could create something special, but I think I can admit defeat here without a hit to my ego. The analysis process can be daunting and many environments are not friendly to getting accurate data. You'll definitely figure this out if you embark on your project.
4. You can run into problems that will ruin a speaker and won't know till you make it - I made some big three way speakers that are basically paper weights because of a resonance problem that I'm unable to fix. I have fairly high standards for what I need a speaker to do and sadly with most resonances, once you hear them you can't unhear them.
5. It's hard to make something better than what you can buy for the same costs - Companies that make speakers have time and money to throw at making prototypes, I wager the average person doesn't have either of those things in the order that a manufacturer does. I tried quite hard to make some great speakers but ultimately none sounded as good as my friends Kali LP6. I make music and I often just go to his place to work on a mix, which is why I'm going to place an order for either LP6 or LP8 soon which will be augmented by subwoofers.
6. I fought the science and the science won - A lot of my speaker builds are more spur of the moment things that could probably use more preparation and thought before the build starts. Many times I ignored things like optimizing off axis response which I should have taken into consideration more or simply underestimated how the issues would effect the final product.
7. Drawers full of useless parts - At this point I consider myself at the end of my DIY journey. I learned a lot, but I feel I mostly learned that I find DIY far too cumbersome and time consuming to be worth it. I stare at my drawers full of drivers that are too cheap to justify the shipping costs to sell, and there is no market other than giving away my less adequate designs. What is one to do with all this waste?
Ultimately though I find that building speakers has really cut into my enjoyment of music. Part of me says "keep going, you're almost there" but this feels almost like an addiction that will never pay off and leave me fully satisfied. This may be over dramatic but as someone who loves to overthink and is usually a perfectionist to a huge fault, I was genuinely in tears recently considering all the time and money I had spent over the years trying to best even some $400/pair monitors and coming up short. I feel as though DIY for me has turned into something that has stifled my own personal growth. I've met some other DIY speaker folk in person and often times I feel like I see some similar things, it's like an addiction for them as well and their relationships appear to suffer. Being a musician, my musical output has declined dramatically since entering the DIY space and I feel more unsatisfied with life than ever. Nothing brings me more joy than creating music, and nothing gets in the way of that more than trying to build speakers it seems. The thought that I can just stop at any time though has been freeing and I must entertain the idea rather than walk by my pile of drivers and wonder what I could do with them.
I'd really love to hear what people think, not so much on the technical criticisms of it all, but the more personal and spiritual aspects I described.
I'm certainly not good at DIY although I hope to be eventually. There are every type of DIYer, from lousy to fantastic. Some only build others designs but it is great for creativity, design, and using your hands to make something. If I want to try an open baffle, a waveguide, cardioid, sealed vs ported, extended bass shelf, etc. I just do it. I'm also fortunate that my wife is very tolerant of my audio hobby of things I build versus finished commercial products. 
