<p>Retention rates sometime are set very low on purpose. One of my first classes at CC was designed to give passing grade to only about 30% of the class because computer lab could not hold more people. It does not mean that 30% who survived were above average people. They were ordinary people with above average work ethic.
Yes, any reasonable colleg math class is more difficult to kids in this country because HS does not prepare them to proper levels. My nephew who is teaching 2nd year math at U of Chicago has mentioned that. Many profs in my classes have mentioned that, adding that problem is getting worse. Again, many who realize that and got help in college, overcame this deficiency, others fell out of their programs. </p>
<p>As I have mentioned, everybody has their own personal references, which explain difference in opinions. However, setting goals high will help, setting them low might derail your goal completely. Whatever approach is, do not create artificial obstacles in your life.</p>