Surveys underestimated the CPI(M)'s decades-old cadre structure. The party's ability to mobilise voters on polling day — especially in rural and semi-urban areas — translated into votes that phone and online surveys missed.

Most surveys were conducted 2–6 weeks before polling. The final days saw LDF consolidation, partly driven by PM Modi's aggressive campaign in Kerala which may have triggered pro-LDF/anti-NDA consolidation among minority voters.

Sampling in Kerala's diverse religious and caste composition is notoriously complex. Agencies may have over-represented urban, upper-class, and social-media-active respondents who were more favourable to UDF.

High-profile controversies (Sabarimala gold, NDA cash-for-votes allegations, Wayanad relief funds row) created visible anti-incumbency that surveys picked up but which did not translate proportionally into votes against LDF.

The exceptionally high turnout (78.27% vs 74.06% in 2021) was not anticipated by most polls. Higher turnout in Kerala has historically favoured the LDF, which benefits from higher mobilisation among its core rural and working-class voter base.

Surveys projected NDA winning 1–8 seats. The actual result (0 seats) meant Hindu nationalist votes were split rather than consolidated. Conversely, IUML voters and Christians who might have considered NDA returned to UDF, not LDF — partly explaining UDF's position.