Printing is not one thing
Printing is not only printing leaflets, business cards or large banners - it also prints other, necessary materials such as: stickers, self-adhesive letters or labels. In principle, everything that comes out of the printing house can be included in the category of printing.
There are plants specializing in the production of only a specific group of printed materials: eg leaflets, or only large-format printing. However, this results from a simple thing: for every type of printing you need to have the right machine, and these take up space and cost a lot. That is why printing plants limit the amount of services provided.
Standards in every industry and business are important. Imagine that we buy a monitor and its input does not match our video card, even though it has the same type. That's why certain standards apply.
In polygraphy and graphics, such standards also exist - appropriate definitions of CMYK colors - key for the appropriate color reproduction. Specified in advance formats for printing leaflets and business cards, so that they are comfortable and as uniform as possible. Without standards, even leaflets could be completely unreadable and even repulsive.
Inkjet printers are highly usable. Printouts made using this type of printers have vivid and clear colors, which is why they are bought by the most specialized photocopying and printing facilities. Such service outlets make a large number of printouts every day, and therefore their owners want to be sure that their devices will not cause any problems during their tasks. I must admit that inkjet printers give them a lot of pleasure and they become the best advertisers of this kind of printers by ordering more and more of them. They look for different models and additional accessories.