Each niche or genre can be different. For mine, it's about putting efficiencies into place that allow me to create consistent content of decent quality. I'm of the mindset that the more I put out there and more topics I cover, the more little gateways into finding my channel there are. I'm huge on the quantity side (because quality is really subjective anyway), but you have to be providing some type of value with each video you post. Value can be informative, entertaining, etc... and as long as you are providing that, I think it's helping you even if the "quality" isn't perfect.
So far it's been proving right for my channel and I'm definitely going to continue down that path. I don't follow any strict schedule, I post when I can as much as I can, and always make sure to provide value above all.