Complex sentence: In some cases, it is chosen for positive reasons, usually by young students with no family commitments; however, for most researchers, it is a form of casualization, which can blight their whole careers and break up their families.
Split into simpler sentences: In some cases is it chosen for positive reasons, usually by young students with no family commitments. However for most researchers it is a form of casualisation which can blight their whole careers and break up their families.