What are the reasons that make sales rise or less is that products itself or marketing or worker productivity or country situation?

Movement in the Sales figures (+/-) has several factors as follows:

1. Demand and supply of the particular product in the market

2. Competitors new promotional offers

3. Marketing strategy

4. Pricing policy of the product

5. Change in the purchasing power of the consumers

6. Global awareness or people become more health conscious (avoid junk food and prefer processed products).

Rise & decrease in Sales could be due to several reasons:

1) Quality of the product 

2) Pricing strategies (the type of the product helps in deciding whether to use skimming,  penetration policy etc.)

3) Inflation

4) Discount offers & schemes 

5) Competitors (Sometimes when there is a new emerging competitor in the market, existing suppliers deliberately offer lower prices inorder to destablize the new competitor).

6) Advertisements (Coca cola spent around $3 billion while & spent around $2 billion each year in the past3 years while aiming to increase market shares of their products)

7) Supply & Demand

8) Purchasing power of the target market

9) Customer Satisfaction 

10)  After sales services 

[A good example might be mobile phone, e.g. iphone5 is being sold in mobile shops for S.R2400 while at axiom they sell it for S.R2500, one person who bought it from normal shops for S.R2400 got his phone broken but they didnot replaced him or fixed the phone for him because it was without any warranty  while the other person who bought it from Axiom was replaced with a new phone & that's the reason people prefer to buy it from reputed and trusted brand].  Nowadays many organisations secures market share only due their after sales service.

some of the factors could include

- Price of the products

-inflation

- Price regulatory policies

-Government policies

-Demand for the goods

-Market competitions

-Supply and availability of the products 

The right product for the right price for the right market

All of the reasons you mention it could rise or lower sales of any product.

The fundamentals of a nation has also got vast influence on the sale of a particular commodity or service. Market is driven by the sources of demand and supply. Price of a commodity or service is one of the determining factors of both supply and demand. And a lot other factors will influence sale