Organic traffic is a kind of immune system for your website. Whatever happens with outdoor advertisement or online advertising methods different than SEO, organic traffic flow will remain constant, or growing steady if you put enough effort. Rapid increase is rather impossible, but the steadiness is a kind of insurance for failure of other marketing techniques.
Many website owners plan aggressive online campaigns, with Google Adwords included, forgetting, that at the moment they stop paying their traffic go back to very low level, low and unusable. What does this unusable level mean? We could describe low organic traffic flow as amount of traffic, which – specific for your business niche – is unusable from statistical point of view. It means, that you can not use it, for instance, for A/B testing or planning redesign of content or website’s navigation. You do need some initial data sufficient for statistics to plan advertising campaigns. Except that the organic traffic gives you rather clear idea of your website perception by search engines.
It seems that wise approach would be to prepare some budget, at least 1/5 of total advertisement budget for some organic SEO work, unles your advertising campaign is based only on paid advertisement. Organic results are not instant, but they will inevitably come. And, in about half year, when your budget pocket will be empty, organic, inbound traffic will start producing more and more effectively new valuable customers.