English to Japanese Tech/Engineering Electronics / Elect Eng Indicators on an operating panel

The cover switches are placed in four directions, and the indications are also different as follows:

Front cover open: Flashing every 0.1 seconds (ultra speed)
Rear cover open: Flashing every 0.2 seconds (high speed)
Left side cover open: Flashing every one second (medium speed)
Right side cover open: Flashing every two seconds (low speed)
If two or more covers are simultaneously opened, the cover that is most frequently flashing prevails, but it does not always become stable.

In the last sentence, does somebody out there have any idea of what "but it does not always become stable" mean?
I'd greatly appreciate your help.
Many thanks in advance.