All your content, social media, brand, and other online assets that you develop in that process are there to stay. And they keep going up in value as time goes by. Even if you stopped investing in organic search, these assets would still be working for your business. You’d get traffic because you’ve built an ecosystem that fuels itself. Now imagine that you’re generating traffic and you’re paying little to no money for it. Your cost per organic visitor will decrease by many factors as your return increases. Bear in mind that this is a cumulative effect that happens over time. Still, it’s a fantastic position to be in.
Regarding Link Detox, links it diagnoses as Toxic are generally fine as they're either not indexed by Google or have malware/viruses/etc., but I recommend a manual review of any diagnosed as Suspicious. I used it recently to get started cleaning up our backlinks and some legit sites and blogs were under Suspicious simply because they didn't have many links pointing to them.

In 2007, U.S. advertisers spent US $24.6 billion on search engine marketing.[3] In Q2 2015, Google (73.7%) and the Yahoo/Bing (26.3%) partnership accounted for almost 100% of U.S. search engine spend.[4] As of 2006, SEM was growing much faster than traditional advertising and even other channels of online marketing.[5] Managing search campaigns is either done directly with the SEM vendor or through an SEM tool provider. It may also be self-serve or through an advertising agency. As of October 2016, Google leads the global search engine market with a market share of 89.3%. Bing comes second with a market share of 4.36%, Yahoo comes third with a market share of 3.3%, and Chinese search engine Baidu is fourth globally with a share of about 0.68%.[6]
There is limited real estate for the top positions in organic search results. With the amount of content on the web today and the number of competitors you have, it can be hard to get in a top position, even despite your best efforts. If you’re a new business or an existing one trying to build your online presence, SEM/PPC advertising can get you in front of highly targeted customers.
Those who communicate value, attract others who seek that value in that topic. Those who are in the know, have an edge over those who don’t know, and that’s valuable. It helps people get more of what they want and like, and reduce their risk and negative experiences. In business, it’s profitable to have more of the right information than your competitors ahead of time (as long as it’s done and used legally to avoid fines and reprimands like with insider trading). Having valuable information first means you can make moves and investments before competitors, to buy cheaper and/or sell higher.
Search Engine Marketing or SEM encompasses the steps taken to increase relevant traffic to your website, through higher rankings on search engines. Traditional SEM is made up of two processes: “organic” search engine optimization (SEO) and pay-per-click advertising (PPC) (or cost-per-click (CPC)). However, the field of SEM is a changing and expanding field thanks to constant new developments, such as:

Though a long break is never suggested, there are times that money can be shifted and put towards other resources for a short time. A good example would be an online retailer. In the couple of weeks leading up to the Christmas holidays, you are unlikely to get more organic placement than you already have. Besides, the window of opportunity for shipping gifts to arrive before Christmas is ending, and you are heading into a slow season.
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