  We comment on progress in measurements of the Casimir force and discuss what
is the actual reliability of different experiments. In this connection a more
rigorous approach to the usage of such concepts as accuracy, precision, and
measure of agreement between experiment and theory, is presented. We
demonstrate that all measurements of the Casimir force employing spherical
lenses with centimeter-size curvature radii are fundamentally flawed due to the
presence of bubbles and pits on their surfaces. The commonly used formulation
of the proximity force approximation is shown to be inapplicable for
centimeter-size lenses. New expressions for the Casimir force are derived
taking into account surface imperfections. Uncontrollable deviations of the
Casimir force from the values predicted using the assumption of perfect
sphericity vary by a few tens of percent within the separation region from 1 to
$3\,\mu$m. This makes impractical further use of centimeter-size lenses in
experiments on measuring the Casimir force.
