Why is it generally assumed that organic compounds and (liquid) water are a necessity for any form of life?
Of course, all life on earth is based on these things, but that doesn't necessarily mean that something considerable as a life form couldn't arise from complex chemical processes with different elements and at different temperatures.
For example, electronic circuits are non-organic and independent of water, but still capable of complex behavior. Something remotely similar to human-made robots using e.g. sun light as power source might have spawned on a planet with lots of metals and silicone. Of course this exact robots scenario is highly unlikely to occur - in reality their brains/circuits would probably work in a more evolution-friendly way - but you get the gist.
Of course, all life on earth is based on these things, but that doesn't necessarily mean that something considerable as a life form couldn't arise from complex chemical processes with different elements and at different temperatures.
For example, electronic circuits are non-organic and independent of water, but still capable of complex behavior. Something remotely similar to human-made robots using e.g. sun light as power source might have spawned on a planet with lots of metals and silicone. Of course this exact robots scenario is highly unlikely to occur - in reality their brains/circuits would probably work in a more evolution-friendly way - but you get the gist.