Can One Rely on Personality Tests?

I found the test pretty accurate in assessing the personality type. According to it I have a D type personality. Which is translated into someone who is eager to get immediate results, solve problems and overcome obstacles on my way to get the results needed. Sometimes is difficult to accept someones authority, especially if the person does not qualify to be in such position; however I enjoy learning from others' in authority and use some of them as role models for my own progress.
Having characteristics of an I type would help in my carrier as I believe that it can be important to influence or persuade others in order to get to the goal instead of using a direct exercise of power and authority.
It is not quite easy to become a different personality type as well as qualify to be just one type. They normally exist in a mix of two or more, but with one of them being more dominant. I think it is useful to realize that we can do adjustments to our personality but not change it completely since this is not just about being 1 of 4 types, but having certain qualities overall.
Finally, this test can be very useful in determining the approximate type, but used in a conjunction with other test can give a decent overall picture of the personality as a whole.

I visited the blog of my friend Elena, I think the test was pretty accurate to describe her personality, she was an I, which translates into her being very good working in a group and interacting with others in order to make her opinion count; well and she definitely makes a very favorable impression on others.
Unfortunately, I did not get well acquainted with many others, so it would be too subjective for me to make assumptions about their personalities.