Tactic Failure

[Kiko Macheda]

I have been using a tactic with 4 variations all season and it was a great success. I had won 28 drew 3 lost 6 and now all of a suden i have drew 4 then lost 2. Why is this? The teams I have been playing I should have won against. Does this happen often? Or is it just the tactics have been used to long? Any help would be great

 

[someone]

you should change your tactic a bit after some time