As such, NLP is considered one of the most difficult research problems in artificial intelligence. The ability to generate text and issue commands via the spoken word clearly provides great flexibility for the user. This flexibility is particularly important for users with disabilities such as lost limb function or severe arthritis, which render keyboard or mouse use difficult or impossible. VRS therefore frees workers with disabilities to use their skills in tasks heretofore unavailable to them. Of course, there are drawbacks as well.
Security is one issue.
Security is a very important factor in technology, and many companies go to great lengths to ensure that computer systems' security aren't violated. Cost is not an issue, as VRS packages retail around the price of most office software suites. Rather, the main hurdle for VRS systems has been its lack of accuracy at interpreting and representing the spoken word. This is understandable given that speech comprehension is a highly complex skill. While humans, in general, have little difficulty with this, it's quite another thing to develop a computer program to do the same.