"The watchmaker analogy consists of the comparison of some natural phenomenon to a watch. Typically, the analogy is presented as a prelude to the teleological argument and is generally presented as:
The complex inner workings of a watch necessitate an intelligent designer.
As with a watch, the complexity of X (a particular organ or organism, the structure of the solar system, life, the entire universe) necessitates a designer.
In this presentation, the watch analogy (step 1) does not function as a premise to an argument — rather it functions as a rhetorical device and a preamble. Its purpose is to establish the plausibility of the general premise: you can tell, simply by looking at something, whether or not it was the product of intelligent design.
In most formulations of the argument, the characteristic that indicates intelligent design is left implicit. In some formulations, the characteristic is orderliness or complexity (which is a form of order). In other cases it is clearly being designed for a purpose, where clearly is usually left undefined." According to Wikipedia.
This argument is based on a very faulty presupposition. The argument attempts to use probability to prove a designer of the universe. The problem with this line of reasoning is this its not probable. Let me explain:
In order for a complex thing to imply design we would need to see that out of the number of complex things we observe the majority(above 50%) are demonstrably designed. I am being generous with the 50% number I would think it should be higher but we will go with this. So do things we know to be designed outnumber the number of stars, galaxies, black holes, planets, plants, comets, and more. Well the resounding answer is no. The number of things we know to be designed in the universe that are complex pales in comparison to the things we consider complex that have no evidence for a designer and appear to come about naturally.
In the set of watches for example we have seen enough evidence of design that in the watch set it is probable for design. Unfortunately, for this argument the set of watches is not the same as the set of all complex things. Complex things have not been demonstrated to be over 50% designed. That is why whenever you observe something in the set of complex items you need to go a step further and still find further evidence of design, because the probability of complex items being designed has not been proven to be more probable.
Let me provide a further example to demonstrate the failure of this argument. Lets take the set of football's and try to draw a conclusion abut the set of balls(no dirty minds). All footballs are oblong and have points at the end. If someone says they have a football it is reasonable to expect it to have that shape. It may even be reasonable for someone who has only been exposed to footballs to think that all balls will have that shape. Once a person has been exposed to the set of baseballs, soccer balls, beach balls, basketballs, bouncy balls, tennis balls, and golf balls, this stance of expecting a ball to be oblong and have 2 points on it is no longer reasonable or rational. That is the same failure that a person exposed to the facts of the universe makes when they make this argument. You can not attribute a attribute of a subset to a set just because you want to, it is too likely to be flawed.