I suppose this is a moment to allow the stream of thoughts in my mind to coalesce into coherent ideas that can be built upon.
It would seem that humans need some sort of purpose, and whether this is due to some metatruth inherent in the Universe at large, or is simply a coping mechanism of a biological organism with the ability to self reflect and contemplate, it is nevertheless a useful factor to approach and develop in one's life as not only does it present the potential for develop better tools for dealing with life, but it also yields the potential to improve life for all.
Why should one improve life for all?
Well, regardless of whether or not one can verify the existence of other consciousnesses outside of the self, the world seems to operate as though it is true. In fact, it could be said that it is best to approach the world as though the other seemingly conscious beings are, in fact, conscious. It is also best to meet this concept with the interpretation that, in a general sense, one's experience contains many attributes which are fundamental to the experience of all conscious beings. With that in mind, it should be noted that the experience of others and the perception of others has an affect on one's own life and, as such, it should be in the interest of each individual to assume that improvements for the lives of others should result in an improvement in life as a whole, including the life of oneself.
With that out of the way (for now), let's talk about purpose
If one is to choose a purpose which possesses the potential to improve one's life, as well as the life of others, then there are a few areas to expand upon:
Conjecture -
It has been argued that setting oneself up to engage tasks through a structure of purpose, whether by convincing oneself or by going through the sets of thoughts and related actions which can be perceived as being logically bound through a higher level scope which assumes a purpose, is not necessarily the true means by which a human pursues continuity and improvement. This can be argued against, and it may be fruitful to argue both sides, as this might not only reinforce one's modus operandi, but might lead one to new ideas which are better suited to higher achievement.
The case for purpose might involve a few of the following:
So why to start a company?