What would cause a brow lift to drop or be unsuccessful?

As we age, our eyelids naturally sag and droop. A combination approach would be best to see visible improvement. In terms of non-surgical treatment options, I would recommend a Chemical Brow Lift (using Botox, Dysport, Xeomin, or Jeuveau) and filler injections to rejuvenate the temples, eyebrow, eyelid, eye troughs, upper eye hollows, and forehead. I typically combine this with Ultherapy and thread lifting to lift the brow; RF and skin tightening laser treatments to stimulate collagen production and rejuvenate the skin; and laser or superficial RF devices for improvements in texture, color, and any crepey skin around the eyes as needed. In some cases, surgery is the best solution to achieve the desired results. See an expert for a formal consultation. Best, Dr. Emer.​

Thank you for your question. I suggest that you move forward and consult with a board certified facial plastic surgeon because it is the goal of every facial plastic surgeon to determine the right solution for the right person.
Best wishes,

A couple of thoughts.  It sounds like you trust your friend and if she has seen this particular surgeons results and feels that they are good,  then you should be reassured that yours will be too.  The brow can fall a bit following a browlift and the surgical approach to the browlift probably has less to do with the brow falling than the fact that the procedure needs to be executed properly and your surgeon needs to understand the subtleties of your particular anatomy.  The one issue I have is that your plastic surgeon isn't certain if the upper eyelid blepharoplasty will need to be performed until the time of surgery.  Your plastic surgeon should be able to determine this prior to surgery.

There are too many variables to give a straight answer to your question. Is the brow lift being performed through coronal approach or through an endoscopic approach? Is there skin being removed or just being re-suspended? Is also important to address the corrugator and frontalis muscles of the forehead which are the elevator and deppressor muscles which can also affect dropping of the eyebrows. In addition, it's important to know what type of fixation is used for the brow lift to ensure that it does not drop. For many examples of brow lifts, please see the link and the video below

Brow lifting can be done through a blepharoplasty incision, above the brow (very rare cosmetically), and by a forehead lift.  An ethical surgeon will tell or at least list out all the possible issues that can occur that would be viewed as suboptimal results, complications, or adverse events.  This is not to say that serious ones happen often, but it is important to be informed before you consent to undergoing a treatment or surgery.  Some patients with thick, heavy forehead tissues are more prone to the results not lasting as long as patients with thinner tissues.  No facial plastic surgery of the skin is really permanent as age, gravity, sun damage,  and wear/tear can cause the surgical result to regress.  Depending upon the technique, forehead/brow lifting can last 5-10 years and are generally very successful.  You do want a lasting result, but you want it to look natural so be careful and go with a reputable surgeon.  Best regards.