BennyLava -
You can spray all the product you want on the surfaces.. In the pictures you posted, I hope you were using that Meguiars APC at 4:1 at the least...
Depending on the type of dirt, grease, gunk, etc., that is on that surface, AND the product`s ability to remove all of those things, you can sometimes get away with just spraying it, rinsing it and extracting it with your machine..
Now, that seat picture you posted - looks like those seats were NEVER cleaned for years and very dirty people sat in them, and ground very nasty stuff into the seats..
So, looking at that - Before - you started, didnt you think you might need to scrub the seat after you sprayed the APC to help dislodge the nastiness on the seat ???
Automotive cleaning will almost always be harder to do than any other cleaning because its a small closed in area, and some people just trash that area for years and dont care about it ever...
I press down really hard on very dirty, soapy places and key the machine to get the hot water deep in that spot and then release the key and continue to press down to now extract the rinse water that is full of soap and the nasty gunk from that area..
You have to always push the tool down into the surface, evenly, across each pass, if you want the extractor to do its best..
And always make more dry passes to extract the hot rinse water you injected into the surface to remove as much of that now dirty water out along with as much dirt from that section as possible..
If you do this many times, and watch what you are doing, you should see a change in color and if you remember where all the dirt was, you should see less and less of it in that section as you work..
Using an Extractor is also hard work - it does a great job at getting dirt up and out of surfaces, leaving them really clean but you have to work the tools carefully, on the surfaces long enough to get the result you want..
If you are comparing this to the guys that come into your house and move a big stainless wand around cleaning your carpets, you have to remember that they have a huge machine out there in the van that has a couple hundred psi to inject water into and disturb the dirt, and a huge amount of water lift to pull all that water back out along with the dirt, from the bottom of the carpet..
And even then, most of them are just kids that are not really good at this, leave way too much water in your carpeting, and it takes way too long to dry...
Good luck - you can do this - just work your process better, ok ?
Dan F