Why is research assistantship decoupled from masters/phd program? I have just been offered a spot in a 2-year full-time masters program at a university in the US. It is very research-focused with a requirement of only a few courses. In the admissions letter they also offer me a full research assistantship (RA) for up to 12 months and say that graduate students typically receive RA support for 2 years contingent on satisfactory performance. The work from the RA is integrated into the graduate course of study. It is somewhat confusing to me why the RA and the Masters program are kept separate as it seems like almost all students would also be a RA. I have two questions related to this:


What are the benefits of this separation from the university's point of view - Is it mainly the ability to kick out students with bad performance?
I may be able to acquire substantial external funding. The offer letter states that the stipend that I receive as a RA would only supplement any external funding to a specified level, meaning that my overall salary would remain unchanged. However, if I get substantial funding this could perhaps allow me to not have a RA/TA position for 3-12 months. Would this be of any use to me? For instance, could I perhaps not have an RA position over the summer to allow me to get some time off?


Edit: This is a prestigious university and my sense is that the department/research group does have good enough finances to provide funding for both years.

2. Edit: The funding is unconditional in the sense that it is simply awarded towards the masters degree without any specific requirements. It is a tradition in my home country to award young students with scholarships to assist them in taking education elsewhere. The organizations providing the scholarships then hope that these students return to their home country after their studies abroad (which many do).
This is very difficult to answer authoritatively because each program is different but here are some reasons:


As @Brian Borchers noted, sometimes the admissions and RA funding committees are separate. At some universities, admissions is handled by the department while the RA funding has to be petitioned from the graduate school.
At some places, the lack of funding in the 2+ year is a weeding mechanism. Weaker students aren't offered funding, so they are disappeared (or they pay full fare which is even better than disappearing).
University or department finances may be such that they are not permitted to make a 2 year commitment. They hope that funding will continue but they are being cautious.
They may hope that rather than a university RA position, you will be switched to an external grant funded RA position. They can make a stronger case for funding "unfunded" students this way.
Something else.


The best thing for you to do is to talk to the director of graduate studies AS WELL AS to current graduate students in the program. People on the internet can't tell you which scenario it might be.