Given following log snippets, their explanation, and nothing else, explain what failure, if any, occurred during build of this package.

  Snippets are in a format of [X] : [Y], where [X] is a log snippet, and [Y] is the explanation.

  Snippets are delimited with '================'.

  Drawing on information from all snippets, provide a concise explanation of the issue and recommend a solution.

  Explanation of the issue, and recommended solution, should take a handful of sentences.

  Snippets:

  [    File not found: /builddir/build/BUILD/udpcast-20211207-build/BUILDROOT/usr/bin/udp-sender
    File not found: /builddir/build/BUILD/udpcast-20211207-build/BUILDROOT/usr/bin/udp-receiver
]: [File not found: /builddir/build/BUILD/udpcast-20211207-build/BUILDROOT/usr/bin/udp-sender and File not found: /builddir/build/BUILD/udpcast-20211207-build/BUILDROOT/usr/bin/udp-receiver: These lines tell you the specific files that are missing. The path /builddir/build/BUILD/udpcast-20211207-build/BUILDROOT is crucial. This is the root directory where the package will be "installed" during the build process. It's a temporary staging area. The RPM build process expects to find the udp-sender and udp-receiver executables within this staging area, specifically in the usr/bin subdirectory.]

Issue: This RPM build failure message tells you exactly what's wrong: the RPM package is trying to include the files /usr/bin/udp-sender and /usr/bin/udp-receiver, but the build process can't find them where it expects them to be. 
Resolution: The most likely reason is that the udpcast software isn't being compiled and installed correctly within the build environment.  The RPM spec file (the instructions for building the RPM) is supposed to handle this.  The build process should compile the source code, and then install the resulting executables into the BUILDROOT directory.  If this installation step is failing or is missing, the files won't be there.