What are the advantages and disadvantages for companies to continuously update their product lines?

There are many upsides and downsides to companies changing their things. I think the upside for a company is they would increase their products, their product lines, they'd also increase their sales and revenue, which is I think what every company is looking for in the marketplace. By supplying more products to customers, customers might be more satisfied and might find better use with the newer product. The disadvantage for the company could be that they have extra expenses by tooling up a factory to change a product. They need to make some major changes they cost an arm and a leg. So I think these costs are then passed onto customers and there is the disadvantage. The disadvantage is not necessarily for the company but the disadvantage would sit with the customer who now has to actually food the bill for the actual improvement on the product. And those are just some of the advantages and disadvantages of changing their products continuously.