You would be surprised but there are people who take time to fill in the application form on line etc and then don't do enough prep for the interview. I was speaking to one person that I know who has recently been out to DXB for the 3 day selection process. He did put a lot of effort into the prep and did his homework on EK.... he deserves to do well. However he ended up talking to one fellow British applicant who did not do that much prep on the companies stats, figures, routes etc etc. Holes in your EK knowledge are bound to be found out and I am sure it will be very clear for HR to determine who has and who has not put in the required prep for the interview.
I think Cerberus's comments are valid:
Some folks expect to just walk into a job because of their experience. The 'I'm a great pilot they must want me' syndrome. If they are not committed to Emirates, why should Emirates commit to them.
A lack of effort strikes me as being a real wasted opportunity. EK IMHO is the best outfit to work for. Its popularity is shown in the sheer number of completed on line application forms it has received to date!
MG