There are several problems with goal setting, especially when it comes to material accomplishments.
First, we mistakenly assume that achieving a particular goal will make us happier, once and for all. But, on the contrary, happiness level returns to normal not long after attaining the desired thing.
Second, we choose objectives - more often than not - that lie beyond our direct and complete control. Consequently, we condemn ourselves to dependence on circumstances. As Seneca wrote, we strive for what is in Fortune's hands, missing out on what is still in our hands. We trade the time of the present for the hopes of the future.
Third, in trying to achieve something, we tend to ignore other aspects of our lives. Behind this tendency are the natural mechanisms of our brain's prefrontal cortex and neural networks. As described in the book The Distracted Mind, which I am currently reading, goals affect not only our actions but also our perception - distorting it by inhibiting irrelevant information.
What should we do, then? Not set targets at all? We can't do that. The same book explains that we have goal-setting capabilities, thanks to our developed prefrontal cortex. It is what separates us from the animals. It is what determines how we affect the world around us. Without purpose, we fall prey to the impulses and challenges of daily life, reacting to external events, as our minds are very easily distracted.
Setting objectives is necessary, therefore. But I would offer a few suggestions on avoiding the problems mentioned earlier.
Goals should be balanced. In addition to career growth and material well-being, it is necessary to consider other areas of our life: self-development, family, social life, health, leisure, etc. Perhaps even prioritize these over other things.
The process of achieving something should bring satisfaction. What is the point of moving toward a goal if you feel utterly unsatisfied in the process? Someone will mention the delayed gratification. But I would answer that one does not prevent the other. We can move towards something serious, postponing a sizeable reward, but still receive small portions of the reward in the present. For example, learning a new language will bring tangible results only in a few years. But even now, one can learn to enjoy each lesson. If we are not satisfied now, then perhaps the target is wrong, or the way to achieve it is not chosen correctly.
Finally, however obvious it is, goals should be achievable and entirely under our control. Instead of setting a goal of doubling our income, as an example, it is better to set a goal of improving our professional skills. The latter is under our control, while the former can happen as a side effect.
To summarize, we need to set goals simply because the daily routines and information flows will take up all of our attention otherwise. But we have to be very careful in choosing each objective so that we don't go in the wrong direction, which can sometimes be worse than having no goals set at all.