While many high school graduates go on to college, some eventually make the difficult decision to drop out. A 2011 National Center for Education Statistics report estimates that only three out of every five four-year college students graduate within six years. Most dropouts leave college before entering their second year, according to the College Scholarships website, because of one or more influential factors.

Rising Tuition

Many simply can’t afford the rising costs of college tuition. Numbers in 2008 from the National Center for Public Policy and Education, cited in "The New York Times," reveal an increase of more than 400 percent in college tuition in the previous 25 years. Within the same time frame, the average family income increased at a much slower rate of less than 150 percent. Some take a leap of faith and believe they will find a way to pay for college as they go along, but soon find out it is not possible. A 2009 study by Public Agenda for the Bill & Melinda Gates Foundation reveals that 31 percent of 22- to 30-year-old college dropouts stated their major reason for leaving college was their inability to afford the education.

Too Much Stress

Even if students can afford tuition, the immense stress, pressure and little sleep some must endure when having to juggle work and school often become too much to bear. This is the number one reason most college students -- 54 percent) -- gave in the Public Agenda study for dropping out and not returning. Because of higher costs for nearly everything, few raises at work and an unstable future in Social Security, fewer and fewer parents are able to support their children through college. In addition to working to afford school, young adults must financially support themselves in making rent, utilities, cell phone and other monthly payments. Nearly six in 10 college dropouts were responsible for paying for their own college education, according to the study.

Insufficient Preparation or Motivation

Transitioning from high school to college can be a rude awakening, as studying, developing time management skills and prioritizing become far more critical. Some students never find a balance between social life and studying. Seventy-three percent of dropouts surveyed by Public Agenda say their high schools failed to provide motivation, preparation and sound advice for going to college. Main obstacles included being overwhelmed by studies, taking required courses believed to be unnecessary, feeling bored and claiming classes were too difficult.

Family Issues

More adults are choosing to return to college while raising children. Because children, spouses and the college-bound parents all feel the effects of that decision, 16 percent of the Public Agenda study participants who dropped out said they needed to spend more time with family. Other strenuous family situations affecting studies include taking care of ill parents or other loved ones and working to help struggling parents make ends meet. The study reveals 53 percent of students who left college cited “family commitments” as the major reason for dropping out. Online courses and more evening, weekend and summer classes can allow those dealing with family issues to still obtain the higher education they desire.