As a lifelong gardener I can confirm that you need to carefully prepare the soil to match the needs of the seeds being planted. Carrots are completely different from corn. And you usually do not make a hole because only a few seeds like corn and beans will grow shoved into a hole.
The right amount of moisture is also critical and is related to seed depth. Shallow seeds like carrots, need frequent light watering so they do not dry out. They must be near the surface or they won't germinate.
And then there are the seeds that need fire to germinate, because a blast of heat helps their shells to weaken. Other seeds need to be kept frozen for a few weeks or have their shells scraped by sandpaper.
And that is only the beginning.
A gardener or a farmer needs to be a scientist.