Running your own Bitcoin node allows you to take full sovereignty over your Bitcoin so that you do not have to trust a third party.
When you run your own node you can ensure your transactions are broadcasted to the network, then validated by miners. A Bitcoin node stores the entire blockchain and validates every block before adding it to the blockchain.
One important factor is that Bitcoin nodes allow users to use the network in a more private and secure way. (Not your keys, not your coins) Not having to rely on a third party gives you freedom and autonomy to interact with the Bitcoin Network.
If you run your own node through Voltage, all peer-to-peer traffic is routed through Tor. This makes your node indistinguishable from other nodes on the network, and other nodes can not see that you are using Voltage.