I thought that would be noteworthy to bring up a point that's a reality, at least in my world. While many folks here appear to rely on the availability of a resale market to recycle their slightly used older product and to partially fund new product, what does one do if there is no resale market?
Assume for a moment that if you buy a product, you're ultimately stuck with it. In that light, an investment becomes much more of a long term commitment where a number of important concerns come to the forefront. Chief among these concerns is product quality and durability, as nobody wants the bottom to drop out in a season or two. Probably no less important is a product's design life and its long term fitness for the task, particularly if it's considered a leading edge product when you buy it. Lastly, although not fundamental to its use and performance, the appearance of a product must appeal to a person's sense of style and character. No doubt, looks can be an important statement, and one would hope that a certain timelessness and vibrancy exists in the graphic design over the long haul.
Now, every day is a new day, and there is always going to be a certain degree of change possible. Usually things follow a pattern of slow evolution rather than the idea of abrupt revolution. Clothes provide an excellent example to work with, because while things are constantly being changed in some way up to four times a year, the core concepts remain relatively unchanged because the basic attributes of the human body really don't change. Of course, even though the idea of what's fashionable and current is driven very hard all the time by the clothing industry, one has to think that a windsurfing board would be more like a bicycle or car where function and purpose can be depended on for long term serviceability and performance.
I guess the question needs to be asked whether one is being left in the dust the following year or two (or maybe even 4-6 years) as you try to realize the value in the product you bought. Although this is certainly an arguable point if one was a pro competitor in the arena with top flight talent looking for any kind positive margin to leverage from, I seriously doubt that the year to year evolution is that meaningful to the average sailor. I think I can say this with a certain degree of confidence, because of my personal experiences. The high wind boards I have been using are at least a 11-12 year old design, and while they could be viewed as a bit narrower and a tad longer, I don't find that I'm being readily dusted by my fellow sailors. Even looking at my slalom boards (one from 1999 and a replacement from late 2006), the performance differences aren't that dramatic. Right now, my newest one is beached due to damage, and I'm back on the old one for a while. Am I disappointed and getting embarrassed by others on the lastest thing? Not hardly.
As I suggested in an earlier post, I think that past products shouldn't be viewed as unfashionable and somehow less potent. I feel that history sometimes doesn't get the recognition and respect it deserves. Over time, products do wear out due to use and must be replaced, I would hope that folks could buy with some confidence and feel proud over the long haul.
I seriously doubt at too many Ferrari owners feel embarrassed by their older model designs.