30 seconds to one minute can be a good length, it depends on where you're placing it. Generally if you're commissioning video it's a good idea to get several different lengths cut (this is relatively easy for an editor to do, and shouldn't increase the budget too much - particularly if you know what you want to include in the shorter versions).

These three elements are most important:

1. Clearly showing what the product is with high quality imagery and what it does (what problem does it solve?)
2. Clearly demonstrating why it is unique or better than other products (without referencing other brands by name)
3. Making it obvious and easy how someone can find out more/buy that product (eg a clickable URL for a YouTube video, as well as including the URL in the video details, and enabling comments so people can ask for more info there)

It's also desirable to:

• Have a good voice over.  I would personally recommend "ABC voices" - trying to sound overly cool or overly cute or folksy/"Aussie" can misfire. A pleasant, warm, professional, articulate voiceover that people associate with the kind of voice that gives them reliable and impartical information (such as the news on ABC) is ideal.
• Use graphics/animation if it's hard to show what the product does - eg think of five razorblades closely shaving facial hair - that's easiest to illustrate by animation
• Include text/subtitles so if someone has the volume down (or is hard of hearing, or has English as a second langauge) you can maximise your communication

Final observation: when placing product video for adverts, eg on YouTube, ensure they are skippable when that's an option available to you. If someone has no interest in your product, there is nothing to be gained by making them sit through a long advert. For example, I sometimes see adverts for industrial machinery which I cannot imagine ever having a need to buy!

 

Would love to hear your thoughts on this question @Beau Ushay @Lisa Creffield !