Started Yardsale, FOBO (YC S11, acquired), Founderkit (side project), SaaS product (18 months from start to acquisition), product and community builder. Raised from top tier VCs, angel investors. Launched Lily.camera ($35MM in pre-sales, biggest launch of 2015). take ideas to launch, fast.
Look at proven, recent examples. There is no one size fits all solution... it's different for every product and launch. Your ability to sniff out the solution to this will be a major factor in how successful your product is. Paul Graham used to ask "how will you get your first 100 users?" in YC interviews... if you couldn't answer it, you probably weren't getting in.