Blood Angel's sometimes have a little spare time from constant war to do their artisan work as they are all artisans in different crafts.
Sanguinius one time spotted a micrometer out of allignement in one of his sons bloodtears on his mask.
There is so much in even the smallest moment of life, so much that humans cannot see. My senses pour down through layers of detail. There is tarnish on the tear drops that sit on the cheeks of Alepheo's mask. There are five droplets. The second droplet is a micron out of alignment. The artisan who made it had been disturbed during the sculpting. The interruption had disrupted his equilibrium. It had taken a heartbeat for him to settle back to his task, but in that time the damage to his work had been done. I can see it in the error, and I can feel the flaw in my heart.
And it bothers him alot lol, must be frustrating as hell noticing every tiny fault in everything and every blood angel are experts in artisan craft so not much fault there but else where it would be annoying.