I have no problem with genuine claimants, of which there must be very few, or else we're a nation with serious, widespread and worrying health problems.
That's the issue. How do you assess someone else's experience in order to determine whether they are genuine? Medical evidence can do so much to weed out the frauds, but then you're left with conditions that are either misunderstood or rife with ambiguity.
For example, how do you assess pain levels? These medical tests and questionnaires don't appear to understand that some conditions vary from day to day or even hour to hour. I may feel great one day and be fit to work, but what about the next day?
How can someone confidently apply for a regular 9-5 job when their medical condition is so unpredictable? That is an example of something that isn't taken into account because these people just can't relate.
Personally, I'm trying to overcome this issue by putting myself in a position to pick and choose based on my needs. Not everyone can do that, though.