Departments Having 1 Credit Introductory Classes

Somebody tweeted that to find out what to major in, students should take the list of majors, eliminate some, and take 1 credit introductory classes in many of them. I attended one school, worked at another, and occasionally look at information about other schools online, and I haven't seen 1 credit introductory classes. How common is it? I see the appeal of being able to try departments like that, but here are downsides I came up with:

1. How much can be taught in a 1 credit class? Students might not be committed to 1 credit classes, and they could have forgotten what they were up to by the time the class meets a week later. Not that it's ever good to fail, but students could show a lack of effort knowing that failing 1 out of 15 credits is a lot better than failing 3 out of 15. There could also be students who want to do well in every class and don't want to try a lot of departments because they don't want their GPA hurt by any class even if it's just 1 credit.

2. A school I worked at makes Incomplete Contracts between a student and his or her professor whenever Incompletes are given, and Incompletes automatically become Fs in one year if the professor does not change them earlier. Should students start their second semester worried about making up an Incomplete in a first semester 1 credit course that the student doesn't need? Having 1 credit classes would increase the amount of time spent by Registrars or others on adding and dropping classes, late grade changes, grade appeals, and anything else unusual.

3. 1 credit classes could cause complications and confusion. Teaching three 1 credit classes may not be the same amount of work as teaching one 3 credit class. For freshmen, is it good if some are taking 15 credits from five 3 credits classes, some from four 3 credit classes and three 1 credit classes, and maybe even some from three 3 credit classes and six 1 credit classes? Having classes only once a week could increase the rate of lateness due to going to the wrong building, bringing the wrong books or homework to class, or something else like that. Freshmen have enough to adjust to without having seven professors, subjects, and buildings to handle rather than five.

4. Will experienced professors want to teach 1 credit classes to students who may not like the department? If the purpose is to show students what later classes in the department will be like, then all other things should be equal, but that may not be possible.

5. Would the 1 credit classes be required of students who declared a major in that department before starting? It would delay how long it takes to get to more advanced classes if students had to take 1 credit class that was a prerequisite for the first 3 credit class. If the 1 credit class was required, what about students who start with AP or other credit for a 3 credit class? Do they get credit for the 1 credit class that wasn't stuff taught in AP? Do they have to take the 1 credit class along with students who don't have credit for a 3 credit class in that department? If the class was optional, would it still be beneficial to take before the first 3 credit class?

6. Is there a better alternative than a 1 credit class? For example, could departments provide a free online mini-course including multiple choices quizzes that could be scored by computers for the purpose of telling students how they did without it counting in GPA. In that way, students could get previews of departments if they wanted, and the mini-courses could be taken whenever the students wanted including in the summer before setting foot on campus. The curriculum of the mini-courses could remain the same or change once a year, so it would require less labor than 1 credit courses taught in person. The mini-courses could let students take however long they want, or have a limit such as having to be finished within three months of starting. Students could be allowed to stop at any point, which is easier than students having to tell the Registrar or other part of the school that they want to drop a class during a semester.