Why do DIY products have less value ?

I would have no problem buying DIY stuff, I would make my own if I had the time, and knew enough about electronics. The whole thing for me is to know what I'm buying. There are already enough scams online. I could tell you that I have a 7' tall majestic speaker that will *blow away* (I love when people use that term) Legacy Whispers or Dynaudio whatevers, only I'm charging 7500 a pair for mine. What a deal, huh? Maybe, depends on who built them, the quality of workmanship, and the sound quality. I can't test all those things unless I see the product before I buy.

I remember a classic ad for Business Week. A guy is hunched forward looking at you, saying, I don't know you. I don't know your product. I don't know your company. I don't know your company's reputation. Now what is it you're trying to sell me? That's what you're up against.

It's not that I'm trying to sell any products. That is just an example of what people think when they look at DIY. By the way, I agree with the ideas expressed above about possibly getting a pig-in-a-poke, with no warranty, no reputation, etc. and those concerns are definitely valid. I guess my main beef is that when someone goes to the extent of trying to do things different or even better than some of the commercial companies, the efforts are looked upon with disdain by many as "tilting with windmills". I suppose that Musicdoc's advise is as good as any, and just not give a damn about the critics and do what needs to be done. I appreciate all the good posts here, and I can see that many of you are pretty cool guys with open minds and good attitudes. So I will forge ahead into new horizons and keep reporting my findings here on the A'gon. Thanks.

As onhwy61 puts it, you are missing out on some very valuable value added items when you buy diy. High end equipment is a little finicky and having a manufacturer there to help is extremely valuable. Lack of support is why I stopped buying diy cars.

For me, Diy stuff is actually more expensive than factory made. My assumption when I buy something and build it myself is that is will essentially be worth nothing monetarily once I am done. It's a little like taking a vacation or paying for education.

Assume a $4000 preamp will have $1000 in parts. I spend $1000 on parts and build it myself. Provided it works, it's probably worth $200 on the used market. I've just spent $800. Fine if your attitude is that you are willing to spend $800 to experience building something yourself, or great if you keep the thing for 20 years or want something unique & flexible.

I like to trade equipment often, so I'm much better off buying that $4000 preamp for $1800, keeping it for a few months then reselling it for $1800 (well, ok MAYBE 1750).

For computers I'm the opposite. I build all my own for the flexibility, experience, fun and knowledge. (Twin Athlon 1800 Win2000AdvSrv clustered motherboards w/switchable 24inch 2048x1200 Sony, shared SCSI drive tower w/6 15,000 rpm U160 36 GB drives & 5 additional scsi's (for multi-os boot), two twin channel adaptec 39160's, 600 gb ide storage.) Spent 3-4K. Couldn't sell it. Don't want to. Perfect system for my needs.

It's all marketing!!! And everyone buys into it!
Everything costs money. Onhwy61 listed a lot of things that are considerations with a purchase. They all cost. With DIY, you fix it yourself. Knowledge is everything.
Remember, most audio companies were started by someone turning a DIY product into a commercial venture.
Also, one cannot compare a DIY cost to a retail cost without multiplying by at least a factor of 10. That's just the cost of business. So, there's a very real difference between Value and Retail Cost, though most folks tend to equate them as equals when they are not.