These days, People are picky about where they put their money. I have met so many people who are so stubborn on their pricing they are never willing to take less, and as a result, they get fewer sales.
I have found that sometimes taking less money or giving things away can dramatically boost your sales.
Whether you are selling body lotion or Kindle books.

Reciprocity

When people get something they often will want to reciprocate, If you go to Subway, They give you a sandwich. You give them money.
Therefore you don't feel you owe Subway anything Because you paid for the sandwich.
Now when someone gives you something no strings attached, You may feel differently. You may feel you owe them a "thank you." Or you may purchase another item.

WHile many people online are giving away freebies. There still seems to be a certain degree of reciprocity involved. You just have to be strategic with it! This can get you more sales, More followers or whatever you are asking from the audience.

Increase Sells And BSR

If you have your product on Amazon, You may know important BSR Is for your sales. This can mean the difference between a bunch of organic sales and hardly any.
When you give your product away for free using a code, It counts as a sale!
If you have a product that needs more sales you can use this method to get more organic sales.
This can be expensive. But if you have a Kindle book you are giving away it's easy to give away hundreds or thousands of copies. But if it's something like a shirt, You may want to consider a discount instead.

Get Email List Sign ups.

People don't realize the value of email list sign ups. When you have a good email list going, you can make a lot of money because you can directly market to those people. You can offer a free product, Like an Ebook, Some added content. Or some sample.
To get people to sign up.

Become More Well Known

People get way excited over free stuff! They will be more likely to remember you. Especially if your store has things in a popular and in demand niche.

Conclusion

Giving your product away for free is a great way to get people to purchase more of your stuff. This is why many authors will give away a couple of their books in a series for free. They hope you'll get into the series and you'll buy the others.