my dear sir, there is a chasm of difference between a conscious and deliberate act of creation and a completely random and chance occurrence. the main objection of theists is, that the components which make up proteins, the very building blocks of life are far too complex to have arisen by chance, for not only do they need to be of the right type, but they also need to be in the correct sequence. like having a huge pile of jelly beans of differing colours, sticking you hand in and pulling out only red ones in a specific sequence, highly improbable i think even the most ardent atheist would agree, this coupled with the fact that eminent french scientist Louis Pastuer demonstrated that life cannot arise in a sterile environment and the concept of irreducible complexity of the living cell which relies on all of its components to function, have convinced some, that life simply could not have arisen by chance. plus there have been various experiments since then to try to recreate the so caled primitive atmoshphere, most notably Stanly miller in the 1950s?, which assumes that the atmosphere was a reducing one (for if oxygen was present in high quantities, apparently this is not conducive for the forming of amino acids as the ultra violate rays from the sun would have destroyed them (it is therefore ASSUMED that it was reducing i.e. not a lot of free oxygen), all make it quite improbable, no let me rephrase that, impossible that life has arisen as a matter of chance, thus we are forced to conclude it was a direct act of creation. you may not agree, but that ok, the reasons are good enough for me.
please note that i am not a scientist, but a humble artist, therefore there may be some inaccuracy, but they represent the basis for the ideas as far as i understand them!