Why do s1ngle hose AC units even exist ?

[tp4tissue]

These are stupidly inefficient.

Using the room air you "just cooled" to cool the compressor,  ontop of creating negative room air pressure which further draws in hot air form the outside ?

WTH ?  Who ever thought this was a good idea.  It doesn't even matter how it's slightly cheaper to produce, the extra electricity it consumes to DO LESS WORK would offset the price difference within 1 season of ownership.

What kind of engineer signed off on this,  They should be ILLEGAL.