I can think of a few situations that really make placements – placements.
One, Social Proof – if the other guy is applying to 10 companies, I should also apply to atleast 10. If the other guy is getting x amount as salary, I would not settle for anything less than 2 times x.
Two Excessive Self Regard - if the other person does not get this job, may be he wasnt upto the mark, may be I am a better student, may be I shall apply.
Three Availability Bias - this company is offering a better profile, this company is a better recruiter, the package is good here, so on and so forth.
Four Envy/Jealousy - Even if I dont get this job, I shall spoil the chances of the other person getting it. Its either me or no one. I shall not let him get it, I hate him, he wasnt good to me !