The number of bars in the signal strength relates directly to performance.

The more bars there are, the better the performance (and longer battery life**).

  0 bars - Camera is not connected. Camera is offline.

  1 bar - Camera is near the limit of its Radio Frequency (RF) range and has a high risk of losing connection to the Arlo Base Station and/or having trouble streaming (e.g. degraded video quality).

**Lower bars also generally mean more power consumption, as information must be transmitted at slower data rates, and often need to be retransmitted, resulting in reduced battery life.

  2 bars - Signal is stronger than 1 bar and there is less chance of disconnection.

  3 bars - Signal is much stronger than 2 bars and there is even less chance of disconnections. Improved streaming experience.  

 4 bars - Strongest Signal with the least chance of disconnects. Best streaming performance.

Another factor that affects performance is interference from other Wi-Fi and non-Wi-Fi devices (e.g. cordless home phones).

You must also consider the signal strength bars against the environment the Arlo system is in. For example: 2 bars on your driveway camera may have a better connection than 2 bars on a similar camera in an office environment that hosts a lot of other wireless technology.