\documentclass{beamer}

\definecolor{Red}{rgb}{1,0,0}

\begin{document}

\begin{frame}
  \Huge
  \begin{minipage}{\textwidth}
    Never Red
  \end{minipage}

  \vfill
  
  \begin{minipage}{\textwidth}
    \begin{itemize}
    \item {\only<1>{\color{Red}}Red on Page 1}
    \item {\only<2>{\color{Red}}Red on Page 2}
    \end{itemize}
  \end{minipage}
\end{frame}

\end{document}
