The question of whether organisms always evolve into more complex forms assumes that simple organisms can evolve into complex forms. This in itself is a postulation with no foundation.
Nature provides countless examples of organisms genetically deteriorating, or devolving, but there is no scientific evidence of species evolving into higher life forms. There is plenty of evidence to show that species can permute laterally in the same way people of different backgrounds can create children with different facial features, height, and skin color. For headstrong Darwinians there is also tremendous hope of the kind that Ponce de Leon had when he was searching for his fountain of youth, but there is no shred of scientific proof to indicate that even the lowest life forms have evolved upward. For those who say there is, they need to check the facts. If they do, they will find that numerous attempts to falsify evidence have eventually and inevitably been debunked sooner or later. Unbelievable many still hold on to false evidence as if it was fact even after it has been discarded. This is why I would plead with scientists to stick to real science and to leave their emotions out of the picture.
Over the past century the scientific community has huffed and puffed over Charles Darwin as if he were some kind of deity. He took basic observations that most children make when they see similarities between living organisms and tried to say something profound. A world bent on eliminating or minimizing God's role in creation has ignored scientific principles such as entropy, and bypassed the scientific process to enshrine his theories in the halls of science. It is almost amusing to watch the indignant posturing and dogmatic struggle that scientists put up as they try to hide the fact that the Emperor has no clothes. Even with respect to carbon dating, many conflicting scientific discoveries such as the nature of the buildup of dust on the moon, suggest that there are flaws to the time lines scientists have applied to Darwin's theories.
Confronted with the facts, many thinking scientists are slowly acknowledging the possibility of "intelligent design" in the universe, but are still reluctant to give God a name. This is unfortunate because throughout history, scientists such as Sir Isaac Newton have made invaluable contributions to man's understanding of the planet and the universe within the framework of a personal philosophy that encompasses the infinite creativity of their Creator.
There is no shame in acknowledging that what we intuitively understand from childhood is true, that is, that there is a Creator behind all we understand and do not understand. Indeed, for every answer to our questions there are ten more questions in science and within the realm of our insight into who we are and why we are here.
Concepts such as irreducible complexity' may be troublesome to some members of the scientific community, but they nonetheless continue to put holes into the neat little boxes scientists like to build for themselves and the world. Irreducible complexity of course is only one example of a myriad of others that demonstrate that the whole notion of evolution of the species is doomed as a theoretical concept.
Despite the ranting of some pseudo-scientists, the theory of evolution needs to be revisited before asking whether organisms always evolve into more complex forms. Needless to say, the whole issue of evolution is a sore point for many not because of the science involved, but because of the moral implications. Most scientists have chosen to believe there is no God, therefore science has to perform gymnastics around Him to try and explain the natural world. At times this can become quite ludicrous, an example being the way in which scientists rationalize the thought process in arguing around the fact that organisms can evolve into more complex forms when the scientific process concludes the opposite.