How important is it to indicate the category of goods in CNC?

Question

Search Engine Optimization

There is an online store.
Each product can be placed in several categories. And the link to it is formed only in one category.
The link to the product looks like:
site.ru/catalog/sport/dlya-doma/gantelya

Periodically, the categories are renamed, moved to other categories, the product moves from category to category. Therefore, the link to the product sometimes changes. I think that each product changes its link to itself every 3-6 months.

The product pages themselves are not purposefully promoted.
There is an idea to abandon the name of the category in the CNC, so that the link to the product is always permanent.
In this case, the link will look like:
site.ru/catalog/gantelya There will be no duplicates
for product names in CNC.

Hence the question of how best in terms of SEO:
1) leave the categories in the CNC, but the links to the product will change periodically
2) remove the category from the CNC, and the links to the product will become permanent

Answer 1

3. Never make urls like site.ru[/catalog/sport/dlya-doma]/gantelya, but always only site.ru[/catalog/sport/dlya-doma]/223322-gantelyaso that the page is always unambiguously addressed through an inalienable unique identifier .
And then links, categories, search engines will deeply care about what has changed or moved where.
The controller, when processing the page, is guided by the id, and compares the current url with the canonical one. and if it doesn't match, then redirect.

Answer 2

2) remove the category from the cnc, and product links will become permanent

Implement this option and close the issue of optimizing product cards and sections, at least from the point of view. URL. Sprinkle the breadcrumbs a bit to show the main category.
There are many disadvantages to option #1 :

1. you can not place one card in several categories, or on the pages of indexed results of the filters;
   
2. frequent change of URL leads to the fact that the accumulated URL of the so-called. "trust" is simply lost and with it the position of cards in the issue.
   
3. nesting increases, which should be minimal (2-3 maximum).
   

Life hack:

1. analyze the search results for promoted queries,
   
2. determine the list of competing sites for a larger number of requests in the TOP
   
3. analyze the URL structure of their product cards.
   

So you will be more confident in accepting the recommendations of specialists.

Answer 3

If your products periodically move from category to category, then for SEO, of course, it would be advisable to make a url like site.ru/catalog/gantelya if you have indexed (! Not necessarily promoted, namely indexed) product pages. Since when a product moves from category to category, the old url will give 404 to search bots and will fall out of the search results, and the new url will obviously take longer to index. And that's bad for SEO.
On the other hand, mentioning the second-level category in the url, in your case sport is also useful for SEO, since this is a keyword and thanks to this, the robot understands which category this page belongs to.
In addition, in some cases, specifying a second-level category can improve the performance of individual pages, since a person will understand exactly whether this is the product that he needs (this is about special cases). For example:

• site.ru/catalog/sport/lenta - it is immediately clear that a sports-related tape means a fitness tape
  
• site.ru/catalog/lenta - you can get traffic with a high percentage of bounces, as people will look for, for example, a ribbon for decoration.