It is considered very good to have the lamp that we light be lit through out the prayer. During Navratra, the lamp if lit till the end of the 9th day is considered to bring lot of luck, happiness, prosperity etc.
The "akhanda deepak" should not be extinguished by itself or by someone, which means it should be lit through out the prayer period which may be more than 24 hours.
Why is this so? What is its actual significance?
As per MrAlien's answer for Why is it best if we light ghee lamp in the house while praying?, its based on Sanskrit saying,
असतोमा सद्गमय। तमसोमा ज्योतिर् गमया। मृत्योर्मामृतं गमय॥ ॐ शांति शांति शांति - बृहदारण्यक उपनिषद् 1.3.28.
But for Akhanda Jyoti/Deepak,
Japa done in front of a akhand jyoti is 1000 times more effective. Deities like Ganesha, hanuman, bhairav and Devi are pleased when worshipped in front of a Jyoti. Akhand Deepak represents your unshakable and unflickering faith in your Isht Devta.
Extinguishing of akhand deepak is considered inauspicious, so be careful in maintaining it. This is an omen that there are upcoming problems. If this happens, light the diya again and do the puja again and increase the count of japa you regularly do to give you strength to fight with the upcoming problem. ( Source:holydrops.com)
This is the same old saying I grown up listening.
