Good question, about how the grub screws can loosen themselves. I never anticipated that would happen until taps actually started blowing off. I don't have a definite answer, but I guess that every time the tap is turned on and off, or the spout turned from side to side, there is a small but repetitive stress placed on the grub screws. It's strange how things do loosen over time with small repetitive stress or vibrations. I image that a tall tap like an echo suffers more stress due to greater leverage than a lower one like the cinnamon. It might be that echos start blowing after about a year and that cinnamons will last longer. But the grub screws ought to stay tight for the life of the tap, say 10 years or even longer. So to be working loose in less than a year is really rubbish.