Weirdest thing a coworker ever explained to you unprompted?

I once heard a journeyman plumber complaining about the state of field work on residential remodels. He was venting because most of the junior crews I see just dump the plumbing lines in the trench and call it a day, ignoring the neccesary slope. He said if the P-trap isn't set with the proper pitch toward the exit, you are going to get nasty gunk and slow drainage issues within a year or two. It is always a headache tracking down who messed up the venting when the whole system starts backing up. That kind of sloppy installation makes the house a nightmare to maintain down the line. I think that’s a real thing that gets passed around, that if you skimp on the basics, you pay for it later in headaches and expensive repairs. It is hard to beleive some people just rely on luck when it comes to drainage.

I remember working on a few older residential builds, and one crew lead always talked about the necessity of using specific sealant on rough openings before any drywall went up. He wasn't talking about caulk for cosmetic fixes at all, but about sealing the perimeter of every single rough opening, like window frames or electrical boxes, with a foam tape or a high-quality expanding foam product. He argued that even a tiny air leak around a fixture could compromise the entire wall cavity's insulation value over time. It felt like an obsessive detail at the time, expecially when the budget was tight and they were rushing to get to the next phase. But after a couple of seasons of working in those cold winter months, I started to see the logic. Those tiny gaps act as direct paths for moisture and drafts to get into the studs. He insisted that addressing the air barrier integrity before the plaster was applied was critical to keeping the building conditioned. It wasn't about making the job look nice; it was about the performance of the envelope. That kind of granular attention to detail is rare in the fast-paced contracting enviornment.

Gonna push back on the plumber story a bit. A P-trap isn't pitched toward anything, that's the whole point of it. It holds water in a U shape and there's no slope to set. What needs the fall is the horizontal drain line downstream of the trap, and venting is a completly seperate thing from slope anyway. Mixing those togehter tells me the journeyman was ranting more than teaching. The general idea that lazy drain work causes callbacks is true enough, I've ripped out enough bellied runs myself, but the details in that story are muddled.

First time posting here so hopefully this fits. Last summer I hired a crew to pour a slab for my shop and one of the guys told me not to let the driver add extra water to the truck to make it easier to spread, said it woud weaken the whole thing. I just nodded because I had no idea what was normal. Looked it up later and he was right, extra water on site does cut the strength. Now I kind of want to test the raccoon latch theory myself, though my dogs would prolly solve that problem first.

The one that stuck with me came from a fence job I helped my uncle on. Older guy setting posts told me to leave small gaps between the pickets because wood soaks up rain and swells, and if you pack them tight they'll push against each other and buckle later. Seemed backwards to me at the time, gaps looked like mistakes. But the fences he built years ago still looked straight while the newer ones on my street got all wavy. Does the same thing apply to wood floors, or is that a diferent situation since they're inside?