Personalised learning aims to improve learning outcomes by adhering to personal needs of learners. The research question of this paper is to discuss how such personal needs can be defined to inform the design of a tool to support personalisation of learning methods in learner-centred personalised learning environments. Therefore two approaches, i.e. the analysis of personality-based factors and task-based factors as indicators of personal needs, are discussed regarding their adequacy. We argue that the analysis of task performance based on clearly defined cognitive tasks is the sounder approach. Further steps how to implement and evaluate a proof-of-concept within the domain of electronic negotiation training conclude our argumentation.