what does "reblog from source" mean? when people ask you to "reblog from source," they are asking you to reblog the post in question from 1) the original creator of the post or 2) the closest blog you can get to the source of the post. they are saying "please don't reblog the post from me. please find another blog in the reblog chain to reblog it from." they don't want to be your hub for all your content. they don't want to be used like a resource blog.
why can't i reblog the post directly from them? why do i have to go through all these loopholes to reblog a post? roleplay blogs in particular rely heavily on notifications / the activity page to keep track of replies and responses to their threads. if you reblog a ton of content from their blog, you crowd their notifications and make it hard to keep track of replies. it's polite to find a non-rp blog and reblog it from them, rather than crowd a roleplayer's activity page with your notifications.
sometimes there might be exceptions. sometimes you can't find a source. sometimes the original poster deleted. sometimes you're passing around an important psa and it's quicker to reblog directly from someone than go find the source. sometimes people don't mind if you reblog a ton from them. sometimes you make a mistake. it's okay. at the end of the day, just be courteous and civil. understand that for some people in the rpc, it's inconsiderate to flood their notifications with reblogs. you might get blocked. please read rules, respect boundaries, and if you can, find another source to reblog the post from. it's just polite.