Police were unable to identify some 90,000 drivers spotted breaking the speed limit, Metro reports.
A camera can be rendered unusable in a matter of minutes by inclement weather conditions. But this is only part of the problem.
According to police spokesman Anders Drugge, it would be possible to identify around 25,000 more drivers if the Swedish Road Authority was a bit quicker with the sponge.
In future the authority will be requested to clean the glass on its camera gantries more than once a week, as is currently the case.