Early last year, I purchased a Roomba (one of those robotic vacuum cleaners that whip around on the floor). Great device! I had some problems with one unit and their customer service sent me a new one out without any hesitation.
Last week, Trish was noting that it didn't seem to be charging properly. I reverified the cord and it worked fine.
Then yesterday, she said "it doesn't work. he starts and then just stops." There was nothing in the user guide (gasp!) on it except "clean the brushes" so after cleaning it out (yes, we do this after EVERY use), I went into Self-test mode to see if that would solve it. Nope - everything seemed to check out. After searching some posts from other users (some positive and some negative), I decided when all else fails, RTFWS - Read the Freaking Support Web Site.
Sure enough - there it was. The Roomba's sensors are all really well placed except for the left one, which is right above one of the brushes - (it uses the sensors for movement and there are left open presumably for more accurate checks). With three dogs and a cat, you can only imagine how dirty it would get. Sure enough, cleaned it out with a little air and a damp cloth, and Rover (the Roomba) was off on his merry way, spinning and turning as he cleaned the floor.
Over the years, I've had a number of vacuum cleaners from expensive ($1500) to dirt cheap ($50), for $200US, the Roomba is well worth the value but be aware: it has to be cleaned just like a computer. If Roomba could do one little thing to improve this device, it would be to provide better tools or technologies for cleaning the Roomba (granted I haven't seen the latest Discovery model).
Include a little screwdriver for undoing the brushes, provide a little brush for cleaning those hard to reach areas, maybe include (or suggest) a can of compressed air - but perhaps most importantly, have the Roomba itself tell you when those sensors are dirty. Most people wouldn't think to look there and its not mentioned clearly in the user guide.