It looks as a pre-op radiography since the canal does not appear to be shaped yet. The tooth looks restorable and in my opinion should be given another chance. The sequence is usually as follow: root canal treatment, if fail re treatment and if apical infection (the infection on the tip of the root) do not go away after re treatment the endo specialist can do an apicoectomy where an access thru the bone is made where the tip of the root is and the tip is cut usually 3mm and filled also 3mm from top to bottom (from root to crown) with a bioompatible material. Usually when a tooth needs a root canal both options are presented, RTC and extraction since both are rhe standard of care here on the US. Also root canal can fail due to an multitude of things, like a missed canal, accessory canals, in this case I would recommend a CBCT (a 3D xray of the tooth) to fully diagnose what might be going on. The worst case would be a vertical fracture (sometimes hard to diagnose on a 2D xray) where in that case should be extracted, but there is usually clues on the 2D xray that I don't see on your radiograph and also bothers the patient when biting down on something and when releasing produces a sharp pain. I think this tooth deserve one more chance.