Front V-neck as a cross-check shows what information is still missing for a back-shape decision. Broad patterned shoulder sections frame a deep front opening, with a pale area visible through its narrow centre. A horizontal decorated line marks the transition to a long, relatively quiet skirt. The person is shown from the front. There is no visible rear outline from which to establish a deep V-back or a particular back fastening.
Use the picture as an example of a follow-up request: can I see the back of this exact dress? Make sure the response does not accidentally show another model. If you like the broad patterned areas at the front, you can then ask whether and how they continue behind the shoulders. Their continuation is not established by this image. Similarly deep front and back openings would need to be compared on the actual candidate. This cross-check prevents several attractive details becoming an unverified complete design. A reasoned choice requires matching front, side and rear views of each dress you are considering.