  We show that for an algebraic reductive group $G$, the partition of a double
Schubert cell in the flag variety $G/B$ defined by Deodhar, and coming from a
Bialynicki-Birula decomposition, is not a stratification in general. We give a
counterexample for a group of type B$_n$, where the closure of some specific
cell of dimension $2n$ has a non-trivial intersection with a cell of dimension
$3n-3$
