Digital technologies simultaneously demand, reflect, and build students’ skills in many old and new areas of learning. They are capable to improve students' learning process as well as students' achievements. New methods need to be developed to use this capacity in a manner that can produce useful and accurate information to teachers for classroom interventions and education system. The second very important element is Human Factor Exclusion. Issues related to Human Factors can arise in any situation and judgment-based analytical process. The outcomes-based on Measurement of Student Ability is very important in national level because they can provide the proof and the evidence-based arguments that the educational system is seeking its aim regarding the assumed learning objectives to the stakeholders (employers, trustees, public officials, accreditation, agencies, students, future candidates, sponsoring companies). During the last ten years, the Latvian education system has used various digital tools for assessing students’ achievements. Digital assessment decisions are used both in diagnostic tests for various age groups and national exams. As schools have the possibility to choose the format of diagnostic tests either on-line or traditional way on paper, it is possible to analyse the differences of the evaluation among them. How significant is the human factor and what impact does it have? What can be the errors of digital systems? What problems are students facing? What mistakes and shortcomings the instruments and design have (e.g. defective items, unreliable answer keys, response patterns)? While most of the studies about these methods are based on data from standardized tests, too less attention is paid to alternative analysis in the real school’s environment. The article analyses and generalizes the difference between the evaluation of students’ achievements by a teacher and by the digital system. Is the digital assessment system changing students’ behaviour during the test? In this paper, we report the results of a four-year-long experiment in diagnostic tests of 6th-grade students in Latvian education system. The most important aim of this article is to compare the difference between an assessment of students’ achievements using digital systems and evaluations done by teachers in a traditional way. The second aim is to analyse the impact of the assessment system for the behaviour of students during the test and how the digital system assists in evaluating students’ abilities.