There is an electrical issue that wasn t addressed...

There is an electrical issue that wasn t addressed . The battery apperantly failed and was replaced. The keyfob was returned to me knowing and wasn t properly working When I got the car home I disconnected the battery , cleaned the terminals . Upon reconnecting the neg cable it sparked with a noticeable discharge.
So now I m investigating a parasitic leak. I do not work as a machanic and recognized an issue ... so how did this get passed a qualified trained tech ?