Because WA-2608 is built-in preamplifier* for outdoor usage. It is different from other antennas， The control box indoor is not an amplifier, but only power supply.
Through the cable, the signal is going form antenna to TV, while the AC current is going form the control box to the antenna amplifier and motor at the same time.
It is very important that, connect the antenna directly to power supply, otherwise, the AC current will be interrupted, and the antenna can't work.
It is good idea to test rotating before installation. Make sure the light on the antenna main unit is on. If the antenna is power on and rotates OK, there should be no problem for the reception.