2) It will always be when you need them.
In 2001 when I first hiked the PCT(Pacific Crest Trail), I had one of those plastic bladders hooked up to a hose system to drink out of as I walked. Even though I bought several of them while I was on the trail every one failed. On 2 of them, the bags leaked, on one, the bite valve leaked and water dribbled down my shirt, another the bite valve came off.
After the first 700 miles of desert on the PCT, water becomes more plentiful until you hit Oregon and then it dries up again. I carried that platypus for probably 800 miles until the day came that I needed the extra water capacity. I filled it with water and…. it leaked.
Sure Platypus will replace your bottle if you send it to them but that’s of no use to me when I’m sitting at the last water source for 33 miles with a leaking plastic bag.
Related post: Water Treatment and Containers