In addiction to George Ishak's answers, it could also be a transient hyperopia due to the change in corneal refraction index caused by an oedema, imho.
Hyperopic surprise is usually seen in short eyes and likely due to the use of inappropriate IOL calculation formulas. Moreover, can occur in emmetropic eye due to the unpredictability of effective lens position.
When the junior doctor who is doing the pre-clerking decides the IOL power without consulting a senior. As these juniors go on changing and do not follow up patients postoperatively, it’s imperative for the consultant to choose the IOL power.