Why reference articles from and/or submit articles to low impact factor journals?
What would be some reasons why researchers would use papers from a low-impact factor journal, say, a journal with IF = 1?


Researchers use papers that are relevant to their research, regardless of where they've been published. Being published in a less prestigious journal doesn't mean the result is less true - it usually means the paper is seen as less significant, usually because the authors/referees/editors think fewer people will be interested in the result.

But sometimes those people are wrong, and a paper is more significant than it appeared, and sometimes the paper may be obscure but it has exactly the thing you need for the work you're doing.

(Also, IF values vary dramatically by field.  The top journals in my subfield have impact factors between 0.6 and 0.7, so an impact factor of 1 doesn't sound low-impact to me at all.)


  Wouldn't all researchers concentrate their efforts on starting their literature search from the highest impact factor journals, and then develop their new work on this basis? That seems logical to me and also most beneficial to a researcher's career in academia.


No, they wouldn't.  Indeed, if everyone else were doing that, a researcher could get a big advantage by being the only person mining paper published in low impact-factor journals for ideas that other people were overlooking.  In my experiences, researchers skim pretty broadly, looking for papers that might suggest new ideas or ways to advance their work, and I've never heard of anyone restricting their reading to the journals with higher impact factors.