This study delves into writing scores in both tests, aiming to uncover the reasons behind score differences. Through comprehensive comparative analysis, this research explores scoring patterns, criteria, and score distributions in IELTS and PTE writing sections. It investigates sources of score variation, including task design, rating criteria, and test administration. This study utilizes interviews as the primary instruments for data collection. The combination of these instruments allows for a comprehensive exploration of the factors leading to disparity scores in writing between the International English Language Testing System (IELTS) and the Pearson Test of English (PTE). The culmination of this journey traverses the intricate pathways of language proficiency assessment, revealing that the writing score differences between PTE and IELTS are not mere numerical variations. They encapsulate a lot of factors, from automated scoring intricacies and assessment criteria nuances to task types and test takers' perspectives. These differences, rather than being divisive, reflect the diverse dimensions of linguistic communication and evaluation. These findings serve as guideposts. They illuminate the nuanced forces that shape candidates' performance, perceptions, and trajectories in these assessments.