(I) Factors of Government Administrative Behavior
At present, the state encourages the eastern developed provinces and cities to change the factor-driven economic growth mode to the technological innovation-driven growth mode in terms of the policy orientation, encourages the eastern regions to develop the tertiary industries such as high-tech industries and modern service industries, and restricts the development of the labor-intensive industries. In 2007, under the premise of high foreign trade deficit, the state carried out a series of adjustments in foreign trade policy and introduced a new product catalog of restricted categories of processing trade. The frequent adjustments in foreign trade policy convey an important signal: the state hopes that a series of trade policy adjustments to guide the gradient transfer and transformation and upgrading of processing trade, and drive the upgrading of China's industrial structure and technological progress.
In the process of transforming to a market economy, local governments are given relatively independent administrative and economic management functions,
Local economic development and interests are directly related to the interests of local governments. The transfer of enterprises from the region may not only result in the loss of capital, the decline of production capacity, the increase of governmental fiscal tax revenue and local unemployment rate, but also affect the industrial structure and regional competitiveness. Therefore, out of self-interest, the government of the transferring region may hinder the transfer of industries from the region to the outside. The government of the receiving place may also be eager to develop the local economy and formulate relatively favorable industrial and tax policies to attract industries to transfer in, and may also ignore factors such as the unadapted local industrial structure and the limitations of the receiving capacity out of self-interest.
(2) Environmental protection factors
At present, the economic development of the Bohai Sea region has entered a relatively high level, the establishment of an environmentally friendly society on the development of a circular economy, in particular, environmental protection requirements are increasing. Many areas, especially in the secondary industry in developed areas of industrial "three wastes" has caused great damage to the local people's living environment, environmental improvement has become one of the important goals of the Bohai Sea region. To practice the scientific concept of development, so that the regional economy to maintain sustainable growth, many regional governments have raised the threshold of environmental protection for potential industries, sunrise industries to make room for the development of space, which will inevitably compress the living space of traditional labor-intensive enterprises, forcing some of them to relocate. On the other hand, factories or companies must increase their investment in environmental protection, which leads to higher production costs.
(C) business survival and development factors
With the development of the economy, the Bohai Sea region's market demand structure will change, the total market demand, similar to food, textiles and other low-processing labor-intensive industry demand for the share of the product will be reduced, while the share of demand for home appliances, transportation and communications equipment, computers and their software, medical and health care products, housing, etc., the share of the demand will grow rapidly. This puts pressure on industrial restructuring. Therefore, enterprises in the region will tend to expand their market space, improve their survival and operation conditions, and enhance their market competitiveness through a certain scale of foreign investment, the establishment of external production and processing sites, the establishment of external sales outlets, and other forms. In addition, industrial clusters can bring external economies of scale and scope, deepen the professional division of labor, reduce transaction costs, etc., which is also an important factor in promoting the transfer and docking of regional industries, and can strengthen the competitiveness of enterprises and enhance the competitive advantage of the region where the cluster is located.
The Bohai Sea Economic Circle refers to the Bohai Sea coastal economic zone dominated by Liaodong Peninsula, Shandong Peninsula, Beijing-Tianjin-Hebei, and extending radiation to Shanxi, Liaoning, Shandong, and east-central Inner Mongolia. Bohai Sea region is China's northern economy is the most active region, belongs to the Northeast, Northwest, North China, since the reform and opening up, the Bohai Sea has formed a well-developed and convenient transportation advantages, a strong industrial base and scientific and technological education advantages, the advantages of rich natural resources, dense backbone of the city clusters and other five major advantages. These advantages at the same time focused on the Bohai Sea region to strengthen the unique advantages of international development cooperation in Northeast Asia. According to statistics, its total economic output is equivalent to 45.3% of that of the Yangtze River Delta Economic Circle and 10% lower than that of the Pearl River Delta Economic Circle. Economists from the comparison of statistics see the gap, but also see the Beijing-Tianjin-Hebei as the representative of the Bohai Sea region has a huge space for development and broad potential for cooperation.