A common question from business owners, and a good one. Of course, the all too familiar response from the digital marketing world (myself included) is “it depends”. There are a lot of factors in play here like budget, business goals, industry, etc.
For the most part though if I had to pick one over the other I would pick SEO. Building a strong organic SEO platform is always recommended for just about any business, but it is a marathon. SEO (search engine optimization) is not a light switch fix for driving traffic, but once it is built you will agree it was worth all the time and money to build it the right way.
PPC is much faster than SEO in terms of results. Done right, a PPC (pay per click) campaign can drive leads to your business very quickly compared to SEO. You are essentially paying the machine to put your ad in front of the right people at the right time. You can also create a backfill of warm leads with a properly built leads campaign, and bring back visitors with some retargeting.
All that said and to keep this short, a great strategy is to launch both at once if your budget allows. You can start driving leads to your business with a PPC campaign while simultaneously building a solid SEO foundation. As your organic leads start coming in from your SEO efforts, you can adjust your ad spend. Or you can put that money towards paying all the employees you are going to need!