Kural - 463

To risk one's all and lose, aiming at added gain,
Is rash affair, from which the wise abstain

Explanation
Wise men will not, in the hopes of profit, undertake works that will consume their principal.

Tamil Transliteration
Aakkam Karudhi Mudhalizhakkum Seyvinai
Ookkaar Arivutai Yaar.