More results when prefiltering in DESeq2

Hello community,

I have been using deseq2 for a while now and as is written in the tutorial, prefiltering is only necessary because of computational power since the results function applies the appropriate filtering.
I have noticed that doing my analysis both ways, without prefiltering or applying a minimal filtering of 10 counts per row, sometimes I can get a few more genes in the prefiltering scenario. And visualizing them in a heatmap those extra genes have a similar image with the rest, that came out in both cases. So visually, the extra genes do seem differentially expressed to me.

I am a bit troubled on which scenario to trust more. Or if both of them are equally correct and it’s just a statistical matter of the amount of genes that you give to the tool and how that affects the padj values of the results.

Many thanks in advance!