There have been, in most recent years, some general changes to the language of some concern. The concern is perhaps not so much for the very usage, but the etymology and the source.
The words "need" and its synonyms have usurped the decision making power of "want" and its synonyms.
"Need" is defined as a necessity; indeed its very usage is a matter of sustenance and consequence and should either be preceded by or followed by a descriptive, narrating the issue further.
The doctor said if I want to live a healthy lifestyle, I need an operation.
She needs to pay more attention if she wants better grades.
In the preceding instances, the reader is introduced to two legitimate concerns. In both circumstances, the reader is given options solely dependent upon actions of the people in each sentence. The person in each does not "need" to do anything, and there are proposed repercussions to their actions or inactions.
This wall needs to be level.
She needs to have her head examined.
In many cases, the word "need" can be used without expounding; however, a reader can be left with a number of questions, rendering the entire sentence useless. It must be addressed that the second sentence in these examples can be colloquial - interpreted as a matter of her questionable sanity.
There is a more insidious matter in the prescribed usage of the words. Indeed, the word "want" expresses a desire; it may be added that "want" can be used in all degrees of desire, but has been substituted in many cases by "need" and vice versa.
I need to get to work.
He needs a new pair of American Eagle dungarees.
The English language in these examples is implicatable of the future welfare of the subjects involved. In the first example, the subject obviously would undergo certain problems should he fail to apply himself to his duties, and again can either be preceded or followed by an explanation:
If I want to keep my job and get a paycheck, I need to get to work.
The speaker knows well that he has options - either choosing to go or not. He understands that there are consequences to his actions.
The second sentence is more concerning than the first, as it deals mainly with consumerism, more so than an underlying obligation as in the first. This form of market-grammar is a means by which corporations both large and small use their goods as necessities to live by. Market-grammar explains a scenario of being without a particular product rendering the consumer very unpopular, and more nefariously rendering him dead.
You need to ask your doctor about Lipitor.
I need an aspirin.
I need a new cell phone.
The issue not being entirely without understanding, is incorrect in its strength - a gross exaggeration. This, as most businesses will know, is a means by which the consumer focuses and breaths. The consumer is made to believe that he or she can not do without. He is made to believe, through his patterns of language distribution - in both passive and active forms, that what is before him is not only a privilege if deemed so, but an absolute right.
Though large corporations are the ones to typically use well crafted marketing techniques, it is not limited to mere commerce but to politics and human sexuality.
By monitoring one's active and passive linguistic mannerisms, one can indeed exercise the capabilities of strength and accountability, not to mention a sense of controlled being. This can be achieved through active engagement with other people, reading, and performing acts of trial and error.