Despite the inefficiency of software processes and products, small software companies (SSCs) enjoy a promising future. These companies are known to have few employees, creating the inefficiency that makes it challenging for the SSCs to adopt effective software practices. This subsequently introduces additional complexity, affecting software engineering processes' adoption. Using the Glaserian Grounded Theory, we conducted interviews (N=18) with participants from SSCs intensively engaged in software development from four countries. We looked for the common traits that are identifiable as antecedents to the number of employees in a company to affect the adoption of software engineering processes. From the participants' experience, five non-technical characteristics (Risk, Competitive advantage, Resilience, Innovative capacity, and Management ability) emerged, complementing the number of employees to affect the process during software practice in SSCs. By the end of this study, we developed five hypotheses for predicting and explaining the adoption of software engineering processes by small software companies.