Because most new products are based on previous ones, engineers and product managers must decide the importance of new features versus compatibility.
Ralph Waldo Emerson wrote, "A foolish consistency is the hobgoblin of little minds," more than 170 years ago. Unfortunately, this is the crux of new product definitions today. How compatible with existing products should your new product be?
The thought today is to get products to market as quickly as possible. But, all new products build on the previous ones. Yes, there are really new breakthroughs that are blank sheets of paper, but even here we are setting a precedent and thinking of what will follow.
Most of Data Translation's data-acquisition products offer increased capabilities, such as faster throughput, higher accuracy, and higher levels of isolation than previous models. The issues that really vex us, though, are the capabilities of new features. For example, different triggering modes, advanced methods for users to interact with data measurement in their applications, large lower-cost FIFO (first-in/first-out) buffers that allow on-board waveform storage, reconfiguring digital I/O, etc. You've probably faced compatibility issues as well.
Another area of compatibility is the issue of obsolete components or even "upgrades" from things like die shrinking. Our engineers, like many others, must replace a component with some other, and often there are added features we don't want. Die shrinking potentially lowers cost, but the increase in speed that results makes it more susceptible to power-supply noise or high-frequency noise on analog signals.
There are always real improvements possible in new designs. These offer advantages for the user to offer expanded applications that "lure" their users.
The issue always turns on compatibility and the time and resources it takes to support any new "perceived" improvements. Being compatible with older designs is an advantage in itself. The ideal design offers the new capability without disturbing current users. That way, the existing user can use the product as is, while the user looking for new advanced methods can use it as well.
Intel maintained compatibility with its 8086 CPU architecture, giving time for the PC market to grow without leaving users behind.
Some of the best ideas come from our customers. For example, we have been offering USB modules for vibration measurement. They are all supported by our QuickDAQ software. Some customers have asked for more triggering to support pre/post/about measurement. These improvements mean that existing infrastructure software must be changed, application software upgraded, then this new software must be gone through and qualified so as not to disturb current users. The only issue for us is engineering time and resources. The customer must then determine whether these new capabilities are worth the time and resources as well.
We tell ourselves that we can't be constrained in a tight box to fit into older designs. Yet we know that change will bring unknown problems. But this is the price of progress. As Emerson further said:
The other terror that scares us from self-trust is our consistency; a reverence for our past act or word, because the eyes of others have no other data for computing our orbit than our past acts, and we are loath to disappoint them.
So, our approach is to offer the new capability for those users who desire it, while being compatible to the old. It takes longer and is more difficult to achieve than a completely new design, but it moves us and our customers ahead. We do know that at some future time, we'll devote our energies to new approaches, but maintaining compatibility gives our customers time to adapt and figure out the best path forward for them.
There are many prominent examples of moving your customers to new capabilities while building on the older ones. Intel did this for years with the 8086 chip family, continuing with improved versions that offered higher levels of performance. More recently, Apple faces such a dilemma with its new iPhone designs, keeping compatibility with older models, yet offering new capabilities for eager customers.
Although Apple changed connector sizes with the iPhone 5, we can still use our old 30-pin connectors through adapters. When Apple introduced iOS7, it left iPhone 3GS users behind.
Perhaps we can think of others who didn't do quite as good a job, but I'll let you ruminate on that.