Your house has a bunch of shutoff valves you've never touched and some of them are already failing

Every fixture in your house has its own shutoff valve. Toilets, sinks, washing machine, dishwasher, water heater, ice maker, outside spigots. Most people never turn any of them unless something breaks and by then half of them don't work.

The problem with shutoff valves is they don't fail in a dramatic way. They fail quietly. The packing around the stem dries out and starts seeping. A tiny drip runs down the valve body and onto the floor or into the cabinet base below it. Not enough to puddle. Just enough to keep the area damp. Over months that slow seep rots out the bottom of a vanity cabinet, warps the flooring under a toilet, or corrodes the valve itself to the point where it crumbles when you finally try to turn it during an actual emergency.

The other way they fail is they just seize. Gate valves are the worst for this. That round handle that takes multiple turns to close. If it sits in one position for five or ten years the stem corrodes and the gate inside freezes in place. You find this out when a supply line bursts and you grab the valve and it won't move. Now you're running to the main shutoff while water is pouring out of the wall.

Quarter turn ball valves are better but they're not immune. The handle can get stiff if it sits for years without being moved. The seals inside can deteriorate. They're still a massive upgrade over gate valves in terms of reliability but they need to be exercised once in a while too.

Go around your house this weekend. Every valve you can find, turn it closed, then open it back up. Under every sink, behind every toilet, behind the washing machine, at the water heater. If any of them drip from the stem when you turn them, that packing is failing and the valve needs attention. If any of them won't turn at all, you've found a problem before it found you.

While you're at it, look at the supply lines connected to those valves. If you see the old chrome ribbed supply lines or gray plastic ones, replace them with braided stainless steel. The old style lines get brittle and crack. Braided stainless is cheap and lasts significantly longer. The supply line under a toilet or sink is one of the most common sources of catastrophic water damage in a house because when they fail the water runs until someone shuts it off. If the valve behind it is seized, that could be a long time.

If you have gate valves anywhere in the house and they're old, consider having a plumber swap them for quarter turn ball valves next time they're out for anything else. It's usually a quick add on to whatever job they're already doing and it gives you valves that actually work when you need them.

Nobody thinks about shutoff valves until they need one to work. Five minutes of checking them now means they'll actually do their job when it matters.