Choose the right USB drive capacity.
Sizing a USB drive has a capacity question and a format question, and the format one catches people out. FAT32 refuses any single file above four gigabytes regardless of free space, which breaks disk images and long video files, so exFAT is the practical default for cross-platform use. Capacity adds a ten percent working margin plus the seven percent lost to the decimal-to-binary unit difference.
Capacity required
Required GB = (files to carry + installer image) x 1.1, then matched against usable capacity of 93 percent of the labelled size
Filesystem constraint
FAT32 fails when the largest single file exceeds 4 GB; exFAT and NTFS have no practical limit
exFAT for drives shared between Windows, macOS and Linux with files over four gigabytes. FAT32 only when maximum compatibility with older devices matters and every file is small.
Manufacturers count gigabytes as a billion bytes while the operating system displays gibibytes. Formatting overhead removes a little more. The drive is as advertised.