I read this, this and this post, however my situation is little different than all of these. Mine is a preemptive question.
I am working as a data analyst. I'm expecting a lay-off at my current company due to cut backs in my department. I have been working here for about 2.5 years. As of now, I have accepted another job, however, I already am aware that it will involve manual work, will give me little opportunity to learn new technologies and I will be under-paid (slightly below average). I am on a work-visa so the day I become unemployed, I have to leave the country. Because of this, I cannot wait to find out if I've been affected in the lay-off. So I was forced to accept this position because nothing else materialized. I didn't apply for this position - it sort of fell in my lap. I'm not being provided any relocation or sign-on bonus so I do not have to refund the employer if I leave.
While I am aware that I can always ask for a better project/opportunity once I join, I don't expect good work to come my way because I know the stage of project they are in - there is no interesting work. Sticking it out might mean nothing for me because this is a 12-month contract.
As I already mentioned, this job will be a step-down and I will continue my job-search. I am aware that if I change my mind anytime between signing the offer letter till only a few weeks into the new job, I burn that bridge. I am willing to take that risk for a considerably better opportunity.
The positive aspect of this job besides the employment is that it will give me a chance to relocate to an area where there are many more options for my skills.
I do not want to omit this (potentially) short-term employment. Such omissions usually turn out badly during immigration processes. That is something I absolutely cannot risk. My question is how do I explain to a potential employer why I'm looking to move out immediately after joining without coming off as flaky and without bad-mouthing my employer?