What makes it so hard to understand, as an intuitive matter, how life would evolve out of the primordial soup is that the molecular building blocks of life, the organic compounds from which cells form, do not behave at all like the objects we encounter in daily life.
If we take a bunch of junk from our everyday lives—some china, a bike or two, some furniture, some clothes, and so on—and throw it together in a vast cauldron and shake it up, nothing much is going to happen, apart from some shattering, even if we shake it for a very long time.
What makes the molecular building blocks of life different is that they react with each other, they stick and unstick and pass energy through each other and spontaneously fold up or unfold. My bike and my desk don’t do that.
To imagine equivalents of these molecular building blocks in our world, we would need to think of physical objects that, while still dead and mechanistic in their nature, would have fairy-like qualities to them. My bike might normally be inert, for example, except when it comes into contact with styrofoam, in which case the wheel would spin like crazy, shredding the styrofoam to pieces. My desk would need to have a tendency to lose its legs when it comes into contact with my china, after which it would need to have a tendency to stick to any car tires into which it comes into contact, but not before. And so on.
My things would, in other words, need to act a bit like windup toys, bumping around in mechanistic ways, but also managing to get wound and rewound through mechanical encounters with each other and with the environment.
(Of course, the physical things I encounter in my lived experience are just themselves agglomerations of molecules, so in a sense there is not really a difference in kind between the molecular world and the world of my lived experience. But the physical things I encounter in my world are generally great big uniform clumps of certain molecules—they are lots of steel or lots of plastic—rather than mixes of molecules that are likely to react with each other. Indeed, the molecular components of my things are specifically chosen not to react with other things. If my desk were capable of quickly changing its chemical composition when it comes into contact with oxygen, as the molecules involved in life sometimes do, then I wouldn’t consider it a very good desk. And so if we look to these physical things for intuition regarding the inevitability of life, we come up empty.)