All good answers above....as usual, I have nothing really to add to those comments.
Was the oversized welds due to chasing undercut?
I have seen welders forget to turn the machine down and weld something much thinner and undercut at the toes so they add additional passes to fill in and end up with larger multi-pass welds where a single 1/4" fillet was required.
And then I have also inspected welds where the drawing called for 1/2" fillets at some joints and 1/4" fillets at others but the welder didn't pay attention and welded 1/2" fillets where the 1/4" fillets were called out.
I suppose there could be all sorts of reasons as to why the welds were larger than called for.....