I have a question regarding leaves!

[Cannabisseur]

what causes leaves to fold in on themselves like this?

 

[UnknownKoi]

Well to Me From All my Reading it Looks Like Your Over Watering Them .

Plant Abuse Chart
Take a Look at This For Future Reference Regarding Your leaves

 

[PrairiePoet]

with just seeing a single leave hard to tell. Over watering comes to mind.....