Aside from Indium Gallium paste drying out as another post mentioned, it also has significant downsides. A big one is that it's electrically conductive so if i

Aside from Indium Gallium paste drying out as another post mentioned, it also has significant downsides. A big one is that it's electrically conductive so if it gets on the motherboard or oozes off the cpu, it can short out things on the motherboard. Another one is that the gallium in liquid metal will react with metals like aluminum, copper, and nickel and over the long term might cause bad things to occur.