The UK benefits system has been built up over many years, over a range of different government departments, and covers many different needs and philosophies.
This means it's a horrific mess. For years it was not possible to know how much housing benefit you would get before you moved into a property. While I think there are flaws with the free market I can see that crippling it doesn't help at all.
It's really hard to work out if you're getting the correct benefits, or if you're getting too many. (We have a tax credit system. The credits lag real world payment information, and many people get caught with having to repay tax credits.)
There are other flaws. Someone getting voluntary work (improving their chances of getting full time paid employment) is penalised. Someone with MH illness who gets voluntary work as a step back into society gets penalised.
So, the different government departments have been streamlined a bit. The different benefits are being changed, and signals are being sent about acceptable use of the system.
I got a letter, to my name and address, with all my relevant information. It had a phone number. I called the number. They asked me security information, and confirmed my name and address. They sent me a form. I had to fill out the form and return it. That form is an assessment for an interview. I'll attend an interview, which is given by a doctor. That doctor doesn't do any diagnosis, they have a rigid check list which they assess the patient against. ("Can you walk 10 metres unaided?" "Can you stand for ten minutes without pain?"). The form is scored and sent to a decision maker. That is then returned to a bureaucrat, who awards one benefit, or another, or none.
The checklist is flawed - turn up with a dirty t-shirt because you're a lazy slob? You score points. Turn up with an ironed shirt and tie because your crippling OCD and anxiety won't allow you to leave the house otherwise? You lose points.
All of this bureaucracy is very expensive. The system is open to abuse from multiple parties - criminal gangs using dead people's names to claim benefits; people over claiming, or claiming while working, or claiming for something they're not eligible for.
Sweeping away all of this and replacing it with a relatively simple "Does this person exist? Are the eligible for the universal income?" would save so much money, and time, and stress. It would free people to do voluntary work, or small informal projects.
Then we just need a bonfire of the tax / duties system, and get something sane there.