how often do new pictures need to be takenof each model

Model? as in --

fashion?
car?
phone?

Is there a standard number of new pictures?

Please clarify.

products in a grocery store/ no standard

I don't see any reason to take new pictures, unless the packaging changes. An apple looked the same 10 years ago as it does now.

Not the same apple. :-)

To determine how often new pictures need to be taken of each model, you can consider several factors:

1. Purpose: Depending on the purpose of the pictures, you might need to update them more frequently. For example, if the pictures are for a fashion catalog or advertisement, you may need new ones every season or whenever there is a new collection. On the other hand, if the pictures are for a modeling portfolio, they might only need to be updated periodically or when there are significant changes in the model's appearance.

2. Changes in Appearance: Models' appearances can change over time due to factors like hairstyle, weight fluctuations, or aging. Therefore, you should consider how often these changes occur and whether they require new pictures. Some models may require updates more often than others.

3. Industry Standards: Different industries within modeling may have specific requirements for picture updates. For example, fashion agencies may expect regular updates for their models, while commercial or fitness models may not need updates as frequently.

4. Market Trends: Trends in photography, fashion, and modeling can also influence how often new pictures are needed. Keeping up with current styles and techniques can help models maintain a competitive edge.

In summary, the frequency of taking new pictures of each model depends on the purpose of the pictures, changes in the model's appearance, industry standards, and market trends. It is essential to communicate with the model, their agency (if applicable), and relevant stakeholders to determine the appropriate timing for updating their pictures.