sunbusrt plugin requiring multiple re starts

we have downloaded and installed sunburst chart plugin(one of the 12 visualization plugins).
But this plugin required me to restart the server multiple times. It did not get visible in the list of available charts in analyzer at one go. I had to restart the server multiple times for the sunbusrt chart to be available in analyzer chart list.
can anyone please let me know why did that happen ? why it requires multiple re-starts ?