I can’t recall any failures. I just cleaned old .isos off mine after upgrading it to latest Ventoy version. Before cleaning, mine included:
d-installer-live.x86_64.iso
KNOPPIX_V9.1DVD-2021-01-25-EN.iso
memtest86-cdiso82.iso
MX-19.4_x64.iso
neon-user-20220317-0946.iso
openSUSE-Leap-15.2-DVD-x86_64.iso
openSUSE-Leap-15.5-DVD-x86_64-20230731.iso
openSUSE-Leap-15.5-Rescue-CD-x86_64-20230731.iso
openSUSE-Tumbleweed-DVD-x86_64-Snapshot20230318-Media.iso
openSUSE-Tumbleweed-Rescue-CD-x86_64-20230731-Media.iso
openSUSE-Tumbleweed-Rescue-CD-x86_64-Snapshot20230318-Media.iso
seaToolsDOS223ALL.ISO