I lived through this transition and I truly don’t recall any of the issues with ball mice. They always worked fine for me.<p>You had to clean out the ball every now and then, but I have to clean off my optical sensor fairly regularly, too.
Optical mice existed prior to Microsoft's IntelliMouse.<p>In 1989, I owned an optical mouse (Logitech S9?). The biggest issue was that that mouse required a special gridded mouse pad.
I don't understand why everyone talks about cleaning the ball, whereas for it was the roller which accumulated dirt every time. Gone are the days when we shuddered to use mouse without a mousepad. A truly welcome change indeed.
Oral History of Gary Gordon: <a href="https://www.youtube.com/watch?v=TxxoWhCzIeU" rel="nofollow">https://www.youtube.com/watch?v=TxxoWhCzIeU</a> HP engineer, inventor of the sensor.