Kural - 535

To him who nought foresees, recks not of anything,
The after woe shall sure repentance bring

Explanation
The thoughtless man, who provides not against the calamities that may happen, will afterwards repent for his fault.

Tamil Transliteration
Munnurak Kaavaadhu Izhukkiyaan Thanpizhai
Pinnooru Irangi Vitum.