Finding people with an earnest, project-oriented mentality is hard. A lot of people believe or want to believe they are project-oriented, but are really case-workers, and vice-versa. A good portion of people aren't project- or task- oriented, they're people-oriented and will conform to a project- or case-oriented environment to the extent that it fosters good inter-personal relations.
A small fraction of people are entirely self-oriented: they'll do whatever is necessary to build their self-esteem and satisfy their will to power. They're cancers. One is enough to destroy the team. Filtering-out these bad seeds is the hardest and most important skill a hiring manager (or potential recruit) can develop. Mr. Suster's post isn't particularly helpful in identifying these most toxic individuals: they bind tightly to their hosts and stick through the disease they create, gaining greater responsibilities and better titles.