We stopped hiring "green" kids a while back, it was too much of an issue as most seemed to "Think" they knew it all but failed to have a clue.   They seemed un-willing to stay late, arrive early.   they used up all their PTO within like 3 mo and then complained to HR when we wrote them up for missing work cause they where sick.  it was a cluster-F#Uk to say the least.   we only went thru 4 before we changed the policy.  their was an.. entitlement mentality..   they where all well paid, but seemed to lack the understanding of what it took to gain wisdom.    they complained that several senior developers would take 1 1/2 hr lunch and on some fridays leave like 30 min early..   (their work was completed), ...   they failed to grasp the concept of getting their work done...  like it was someone problem, but not theirs.  and its not "Fair"..
i remember starting out pulling 10-14 hr days for weeks on end , watching others leave, why..  my work was not done, plus i wanted to show i was willing to work to get the job done.   seems our younger crowd lacks this work-ethic.    so we hire senior ppl., who have "paid dues" and are "accountable" for their work.  
we have struggled to find the "sweet spot" last person we are dealing with is a retired school teacher who decided they did not like working for peanuts..  now they struggle with me leaving at 3pm.   he has been told by several ppl, including me.   he is welcome to come in at 5am and leave at 3 as long as his work is done.   and when i get home i get back online and continue to work for 2-3 more hours to keep things moving in the office.  he seems to shut up when thats brought up, but his boss is getting tired of him brining this up, he had gone to HR about time/attendance but the managers have discression..   he is just mad he's not shown any.   not sure if he will last...