\documentclass[11pt]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{enumitem}
\usetheme{default}
\begin{document}
\begin{frame}
\frametitle{Tactics used for career advancement}
\begin{enumerate}
\item Consistently exceed performance expectations
\end{enumerate}
\end{frame}
\end{document}
TeX capacity exceeded, sorry [input stack size=5000]. \end{frame}
Removing the enumitem
package fixes the problem, but in the real life I need that package to remove the left margin. In the real document I use:
\begin{enumerate}[leftmargin=0cm]
enumitem
package with beamer, they are incompatible.\begin{enumerate}[leftmargin=0cm]
leftmargini
instead.