One of the reason why wires aren't generally used as clamps is simply because the single-strand wire would tend to 'cut' into the hose and not apply a uniform force on the surface of the hose it's clamping down on.

This ingenious home-made tool solves that problem and makes it convenient enough for anyone to grab a piece of wire and use it as a hose clamp. The steps however are slightly more involving compared to simply slipping on and tightening a regular hose clamp.

Also, we don't really like the idea of tucking the sharp ends of the wire back into the hose itself as this might damage the hose and cause a leak further down the road, but since it's a great alternative to hose clamps for little to no money,  we really can't complain!