It is usual to get beginners - especially male, who want a 'quick fix,' to be bruce lee, steven seagal etc in a very short time. They want to 'take out' quick-time without realising the amount you have to put in to achieve anything in life - especially a martial art. I think maybe in the case of a uni club there are lots of other things which have to be considered - drinking/socialising/other sports/activities interests available and of course study. It is sometimes hard to prioritise. Aikido in particular does not tend to give 'quick fixes' - safety in practice has to be a priority especially at beginner level and quick fix self defence techniques have to be carefully introduced, which does not suit all beginners. But, maybe they will come back to aikido after they have tried other arts - a lot of people do. We can all teach basic self defence techniques which may include bits from a variety of arts - I sometimes do - even just to show parrallels to a specific aikido movement/technique. This can also be useful in keeping individuals interest, but must be used judiciously or you end up teaching another art?
Sorry would like to continue but lunchtime is over. - maybe later