I think every knitter at some point in their lives has been frustrated by a pattern they couldn't understand. Perhaps the wording was vague and a chart would have helped, or maybe the chart was unclear and written instructions would have been better. Maybe the pattern designer assumed familiarity with a certain technique when a more thorough explanation would have helped.
Though many of these challenges are surmountable, some of them are not. What if the pattern were written in a language completely foreign to you, and translation software weren't much help? What if you were visually impaired and your voice browser couldn't read charts, and no written instructions were provided? What if you simply could not figure out what the designer meant by some terminology, and you couldn't get a hold of the designer? You either would have to go to extraordinary measures to get the pattern to work for you, or, more likely, you would give up and move on to a different pattern.
It's unreasonable for us to expect that designers can write a pattern to fit every knitter's preferences. Even if a designer managed to publish a pattern with written instructions in 5 different languages, a chart, English and metric measurements, summary instructions with detailed explanations, all in 5 different sizes, there may still be factors that she didn't consider.
Consider combination knitting, for instance. Knitters who knit combined tend to prefer that decreases are expressed in terms of their lean rather than the technique itself. For instance, a k2tog to non-combination knitters implies a right-leaning decrease. Under certain circumstances in combination knitting, a k2tog, if taken literally as a technique, will actually produce a left-leaning decrease. One solution would be for a right-leaning k2tog to be expressed in the pattern as k2tog-R. While this may be an optimal notation for a combination knitter, it may be more confusing for a Western knitter unfamiliar with this more uncommon convention. What is optimal for one person is not optimal for another.
Considering the wide range of people's preferences, wouldn't it be great if everyone could use a pattern in the format they wanted most? Wouldn't it be incredible if the knitters themselves were empowered to do this, rather than putting the burden on designers and publishers? Is this too much to ask? Is this impossible?
No, it's not. KnitML can and will solve this problem.