Sorry, you make it sounds like poly lecturers are so noble. No, majority of them are there to slack. Dont believe? Go ask any poly students.
You say all poly compete fiercely for lecturers? I heard there is an unofficial agreement between the polys hr on no poaching of each others lecturer, this is to prevent salary from going up due to job hop.
Your comparison of
moe teacher is weak you should compare both of the same age group. Of newly minted degree holder joining
moe will earn less than 4k.
Moe teachers in their mid 30s would have earn more than 5k to 6k at least.
Poly lecturer is end of career type of job, there will be no more mkt value after a few years(except going to pte sch, but the pay sucks). That explains why the turn over is low.