How come evolution never developed the wheel?

The expectation from evolution is small changes from one generation to the next.
Large changes may occur between different generations from the same chain of ancestors over much longer periods of time. There is no expected goal of evolution.
We are not sure that it came up with everything we know exists. But we do know that there's no better explanation so far. Sure they do.
They predict that evolution will come up with small changes from one generation to the next - and this is observed in every generation that occurs.
They predict that evolution over generations will leave similar looking fossil chains - and this is observed in every fossil that occurs.
They predict that DNA will leave traces over past generations and ancestors, and that this chain will match the similar looking fossil chains - and this is observed in every DNA chain and fossil chain we have the information for.
They predict that many species will not be able to evolve in time to adapt to a change in their environment and die off - and this is observed for many, many species.They do not predict that evolution will create something specific (like "a wheel") because that is not how they think evolution works.
The changes from evolution may end up creating a wheel. Or they may not.
But for anyone to "expect evolution" do just create a wheel - grossly misunderstands how evolution works. What makes you think evolution would create something just because it is a 'relatively simple design?'
Evolution is only expected to create "changes." Some will be good, some will be bad, some won't make a difference. Some will be simple, some will be complex. Do you know what even you expect from evolution?
Earlier you seemed to expect evolution to provide "simple designs." Here you seem to claim that evolution provided "sophisticated designs."Regardless of your own confusion - I think it's clear that you do not understand what Scientists expect from evolution. Actually, the basis for saying evolution has the ability to "make (anything)" is foolish.
Again - evolution doesn't make "things." It just makes "changes."If the changes help, the changes stay.
If the changes don't hurt (enough to kill the creatures before they can reproduce...) the changes stay.
If the changes hurt (enough to kill the creatures before they can reproduce...) the changes die off with the creatures and disappear.

I think Lammy is a girl.

Didn't you read the answers given?Firstly there are some examples in the bacteria flagella and partial ones in the grasshopper's leg. (Also ball and socket joints in mammalian hips).But there are real reasons why wheels aren't generally used.They're only really useful on roadways - evolution didn't have roads to work with. You can't climb with wheels and you can't deal easily with broken territory.Then the wheel needs an axel and a rotating wheel prevents easy inervation and blood supply in the usual way - because cords wind around the axel. A totally different mechanism would need to have evolved. Not impossible, just unecessary and unlikely because it's not a useful feature - because there are no roads.Now, what's wrong with that?I'm interested in why there are no tripods - now why do you think that is?

There are lots of tripods in nature. The most obvious example would be ipnopids (tripodfish): Maybe I'm misunderstanding your meaning here.

Apart from the parrot conjecture, there are no known species where three legs are standard, although the movement of some macropods such as kangaroos, which can alternate between resting their weight on their muscular tails and their two hind legs, may be an example of tripedal locomotion in animals. There are also the tripod fish. Several species of these fish rest on the ocean bottom on two rays from its two pelvic fins and one ray from its caudal fin.[3][/qs]Tripedalism - WikipediaI mean true tripedalism. But that fish is interesting and I had never heard of the parrot conjecture - still haven't.

Wiki seems to give the wrong impression about roos' locomotion. They rest on their hind legs and tails but I have not seen evidence of them moving just with those.
When they want to move slowly such as when feeding they will place their front feet on the ground and supporting themselves on front feet and tails swing their back legs forward, move a bit forward on the back legs then repeat. That I guess would be pentapedalism.

Sorry been a while. Oh my goodness has it been almost a year? Life has been super busy for me. Both husband and I quit our jobs to work full time on our business. Our company is actually making a profit. We are trying our darnest to not become part of the statistics that say most startups don't survive the first 2 years.Anyway, full blooded boy here.