Significant Torque Loss.

You wouldn't, normally, think of a roller-blind as a particularly complicated device to operate.

https://twitterwithbraincells.blogspot.com/2024/06/hmm-my-linen-closet-door-seems-to-have.html

However, apparently, certain people find the almost imperceptible effort involved in lifting your elbow just twice, to gently pull the chain/cord to lift/lower the blind to be too much. So instead you have to yank the chain/cord with all your might. Ripping the chain/cord from its winding. Immediately rendering the blind permanently inoperable.

Even if that then forces someone else to vertically mount a venetian-blind into the recess. Venetian-blinds being the ones with slats you can rotate. Reducing the need for the entire blind to be lifted/lowered. 

Obviously you wouldn't want to mount it all the way into the recess, as that would see it snag on the window latch/handle. Although you would want to mount it far enough into the recess that things can be stored in front of it. Reducing the need for the blind to be lifted/lowered.

Even if that then forces someone to vertically drive 4x20mm screws into 2x21mm brackets. I've not checked but I'm pretty sure the World's Smallest Allen Key™ is still significantly larger than 1mm.

All of which creates incredibly specific sink tidy parameters.