Boat naming is a personal act to associate this new boat into your life.
With children we conduct various ceremonies from the traditional religious events like baptism or bris to the ancient tribal rituals.
John Vigor and others of developed boat naming rituals. Here is one published version. Which has two parts - the Denaming where you remove all references to the old name and then announce to the gods of the sea the new name.
The Coastal people thru the eons have developed rituals to invite good will (spirits) and banish bad things (evils). Shaman, priest, or even the unusual members of a tribe are asked to utter a word or prayer over the inanimate boat to give the boat life. To inspire the boat to connect with the captain. To encourage the boat to be strong when needed and bring the captain home to the tribe when the voyage is done.
Sure you can just grab a can of paint, but when your on the seas beyond the sight of land, our minds can imagine all sorts of strange scary things. That is not the time to wonder, is the name of my boat ok with the ancients or will Neptune send the kraken.