SEO is a long-term solution. You will not get any overnight success or even after a month. This can be a deterrent as it can seem like a sunk cost for the first 6 months.
When you stop conducting SEO work on your site you will still benefit from the work put in and web rankings you have secured. While with Google Ads on the other hand, as soon as you stop, so does your success. However, for best results, it is advised to have a consistent, ongoing SEO strategy.