*3.1. TMT Experience Heterogeneity and Innovation Quality*

As tacit knowledge, TMT experience is both difficult to transfer and difficult to be imitated, which is an important source of enterprise competitiveness. The experience heterogeneity caused by individual differences influences the creation of competitive advantages. According to the upper echelon theory, TMT experience heterogeneity influences the team's perception and interpretation of a given situation, which affects strategic decisions such as enterprise innovation [38]. Based on the existing research, TMT experience heterogeneity can be divided into functional experience heterogeneity and industrial experience heterogeneity [7,39,40].

Functional experience heterogeneity refers to the variations in the professional knowledge resources, experience skills, and modes of thought that TMT members possess depending on their job tasks and functions. The stronger the functional experience heterogeneity is, the greater the differences in the experience of general management, financial management, production management, marketing, and technology among members are [7]. Industrial experience heterogeneity reflects the differences in product processes, technology, and customer needs that TMT members have encountered within the industries in which they have worked [20]. The stronger the heterogeneity of industry experience is, the greater the knowledge differences among members regarding industry regulation, opportunities, threats, competitors, suppliers, and customers are. These two types of heterogeneity have different effects on innovation quality.

The knowledge of market service modes is fully integrated after combining members with different functional experiences. This can improve the quality of team decision making and create complementary benefits in company strategic decision making by reducing knowledge blind spots and developing varied thinking patterns [41,42].

Specifically, team members can first create diverse information-processing views based on their own functional experience thanks to the variability of TMT functional experience. On the one hand, it makes TMT members more sensitive to changes in the internal and external environment, which makes it easier to identify new routes for innovation [41] and lowers its uncertainty. On the other hand, it stimulates the TMT to respond to strategies in time, discourages the TMT from engaging in group thinking [9], and offers more innovative decision-making solutions to enhance innovation quality [43]. Secondly, TMT functional experience heterogeneity can promote innovation change [44]. The professional experience of TMT members is an important basis for TMT decision making. Meanwhile, differentiated functional backgrounds provide various professional knowledge, skills, and ideas for solving problems. The collision of cross-functional experiences can effectively enhance the team's capacity for decision making and problem solving [45], which makes TMT more inclined to implement innovation change and finally improve innovation quality. Therefore, we propose the first hypothesis: Hypothesis 1.
