After college, once you get the first job, start looking for a better job after a year or two. Don't stay out of loyalty.Because trust me, no company is loyal to their employees. Be respectful and professional, but loyalty in a company is rarely noticed and appreciated.
As a person who has worked for a same company for 6 years after graduating, i found out i didn't get a single raise within it unless i ask for it every f*cking year, never got much other benefit than initially signed while studying at school.
So i started applying for 5 months and finally got a job, it pays me almost 5 (edit: 4 is more accurate+ benefits such as health care, lunch, gym etc...) times as much as i used to. My friend from same school, with same seniority was getting 4 times my salary for the last 2 years already.
My mistake was thinking that being loyal to this company was gonna in return make the company loyal to me, the company only wants lower costs, loyalty has no place here.