SEO: SEO works if you want to rank on SERP pages and it somewhere also work for user experience because if you want to rank on google you have to generate best traffic and to generate traffic your website should be user friendly and easy to access, so SEO is all about your website and user experience.
PPC: PPC are basically paying for traffic that platform like Fb or Adwords can generate. if you want direct leads to your business and have unlimited budget then PPC is better for you. If there are any kind of limit in your budget then it will not be fruitful to you.
Thus, both have their advantages and should be used together to get the benefits of both.