there  are a series  of glands on the lids margins. this is the infection of those  glands. suppose one gland get infected and you get treated  but  during  the same period the adjoining  gland get infected. slowly  the infection increases and thus it becomes a series.  to break  this  chain  you will have to use antibiotic eye drops 2hourly for a longer duration ie for months together.

Hello Recurrence of stye has two main reasons A. Diabetes :this might not be the cause in your case B.  Poor lid hygiene Maintain proper lid hygiene by warm compresses followed by lid massage with index finger tightly from up to down followed by application of aziyhromycin ointment over lid margins  will help you Treat any meibomitis if present Use goggles in sunlight and protect your eyes from dust All these measures will help It's lid hygiene which will prevent Recurrence Medicine usually treat stye