This is a very challening question, as I don't know a single person who had attended Lehigh and not liked it. However, I am also very spoiled by my personal experience. I would have to say that the type of person who should NOT go here is one that expects just to float by as a number and get your degree. You will have to work hard for it, and you will be a "person." Also, while being somewhat diverse, it is not an overly diverse and "artsy" school, so people like that may not like it as much.
A student who was attracted to Lehigh simply for their party reputation should not bother attending. The academics are rigorous enough that they would be lost if their only focus was socializing. Any student who was not planning on attending class regularly should look at another school as well. Lehigh faculty get to know their students, partly due to the smaller class sizes, so they know if you are not present for lecture.
There is not a specific type of person that should not attend Lehigh; however, if a student is interested in hands on learning or deep discussion (from day one) in the humanities and social sciences he/she will have to work to find those opportunities. For this student most of his/her entry level classes (taken for the fist two years) are often unsatisfying, impersonal lectures.
Lehigh University is not a liberal arts school. Students interested in Liberal Arts and majors along these lines should not attend. Lehigh is also not a school for those lacking in motivation and intelligence. It is fairly competitive, and the only way to be successful is if you work hard and stay focused throughout all of your academics.
Someone who is not a social person. While this school is very academically focused, the party scene is very dominate and can be a hard adjustment for students who do not party. Also, if you want a really big school, this is not for you.
There is no one who shouldn't attend, but they should be aware of the climate of the school. It' has great engineering and business schools, but the racism and conservatism of the student body might be more than some people can handle.
I honestly don't know, there are plenty of people who I thought liked it here and were doing well who then transferred, so it depends on who you are and how you interact with your school.
A type of person who isn't willing to go outside of their comfort zone. You definitely need to step out and really do things that you normally wouldn't do in order to find what you like.
a person who is willing to be patient during change and someone who will help make lehigh the more accepting and progressive school it wants to be
Someone who has trouble making friends might not fit in the environment too well here and might feel very isolated.