Because having just the Phantom Drophead isn't enough.
Like its direct UK rival Bentley, Rolls-Royce is very much in expansion mode these days. Both are planning SUVs as well as additional variants of existing models. Bentley is even considering an entry-level model. But for Rolls-Royce, the plan forward is apparently going to include a new convertible. Set to go on sale sometime in mid-2016, this as yet-unnamed open-top tourer will share its wheelbase and two-door layout with the Wraith.
However, it won't be just a Wraith without a roof. It will likely have its own unique styling. Rolls-Royce has stated that the model "will deliver effortless, open-top touring through the perfect marriage of modern Rolls-Royce luxury, style and elegance with an engaging and exhilarating driving experience." Obviously pricing is going to be way up there, with sources claiming that it'll likely start at around £250,000. If all goes to plan, expect for this new Rolls to have its official public debut at the 2015 Geneva Motor Show.