I did what you suggested for 2-3 years and never had anything grow. I then planted my tulips about 8" deep and had them come up all over the place! I guess my zone requires it...

Many seeds want light for germination and need to be placed on the surface of the soil.

I use 4 different seed-starting manuals to guide my efforts, finding them most helpful to raise germination percentages of what seem to be ever-more-pricey seeds.

I can't speak to the bulbs issue, but with seeds, it pays to look up information specific to what you are trying to grow.

My fuchsia seeds, I just press onto the surface of the compost. Some seeds need freezing before they will germinate, and others need a good soaking. Some go to extremes like South African plants that need to go through a bush fire and be burned before they start again. Wonderful aren't they.

Happy new year.

John