read numbers in diamond input, output and Megan "no hits"

[rocherbpb]

I understand that diamond output read number may be considerably less than diamond input read number, as the output excludes reads for which no alignment is found i.e. excludes "no hit" reads.
How is it then that reads can end up in the "no hit" node when viewed in Megan?

[bbuchfink]

Maybe the target has no taxonomic assignment or something, but I don't know how Megan works. You can ask your question here: https://megan.cs.uni-tuebingen.de/