You should always be prepared and looking your best because you never know when an important opportunity might arise.
Here's a breakdown of the message and why it's implied:
* The woman applying makeup: This visually establishes the context of beauty and self-presentation.
* Studying her reflection: This suggests a desire to achieve a certain look and perhaps project a certain image.
* "Ladies, you never know when going?": This unfinished sentence implies the woman might go out and meet someone.
In essence, the ad is playing on the idea that appearances matter and that women should be ready for any eventuality – a chance encounter, a special occasion, or simply the possibility of being seen. It uses fear of missing out to encourage sales.