My son goes to Georgia Tech, as most regular posters know by now. It is very unusual for students to graduate in 4 years. Current stats from the College Board is that 79% graduate within 6 years. Students are not referred to as freshman, sophomore, etc. They are referred to as first year, second year, and so on.
Right now, my son is on track to graduate in 4 years, thanks in large part to the number of AP and UConn co-op classes he took in high school for which he received like college course credit at Tech. Really, that is the only way GT students can get their degrees in four years. The academics are extremely rigorous, particularly in the engineering and computer science programs. Tech students have to get a minimum of a C in courses required for their major, and my son had to take one course twice, but only one. He is a good student who fully applies himself, which in any college student makes a difference is success and graduating "on time" or giving up and deciding to drop out. Your college education is what you make of it, just like every thing else in life.
The payback for the longer time to get a degree is that Georgia Tech graduates in the engineering and computer science disciplines are well regarded for the quality of the education they receive and are heavily recruited by some of the biggest names in business. There was a time in the not too distant past when The Walt Disney Company only recruited electrical and mechanical engineers from Georgia Tech. Not from MIT, not from Cal Tech. I heard this first hand during a first year parent orientation session for Tech's College of Computing from a former Disney electrical engineer.
Presently my son has a guaranteed job offer with the software company he did his internship with this past summer. He could take it TODAY (yes, without graduating - but momma said an emphatic" NO" to that!). Microsoft is flying him out to their HQ sometime in the next month or so for a second interview. The first was for an internship for this past summer, this one for a post-graduation full time job. They are skipping over the on-campus interviews that are the normal process. They are recruiting him hard. This is in large part due to his choice of school, and not necessarily driven by his gpa. At 3.0 this is considered very good for Tech. Unfortunately, some companies are still drive by this number and not necessarily the quality of the student and their experience on prior internships (yes, Google, I am talking to you).
Some of the "lesser" schools (in the link by the OP) who have the low graduation rates also have lower admission standards and lower tuition. As a result, they get the students that are not as academically motivated or "gifted" or may not have the financial means to afford a higher education. They may struggle to pass classes or be able to pay the tuition so opt to drop out and enter the working world without a degree. I think these rankings and stories cast an unfair light on those schools and the types of students that attend, who in all likelihood are doing the best they can but struggle in one way or another and opt out. Not everyone is cut out for college. These colleges certainly have a higher percentage of these types of students that deserve kudos for giving it a try anyway. It is unfair to cast the institution as "failing" to graduate students when some of those students were not well suited for success due to personal circumstances.