Section 201(1) of the Income-tax Act, 1961 deals with the consequences faced by an individual or entity who fails to deduct or pay the tax deducted at source (TDS) as required by the Act. When a person responsible for deducting TDS does not do so, or after deducting, fails to pay the tax to the government, they are deemed to be an assessee in default. This section is significant as it ensures compliance with TDS provisions, which are crucial for the timely collection of taxes by the government. The statutory test involves determining whether the deductor has failed in their obligation to deduct or pay TDS. The burden of proof lies with the deductor to demonstrate compliance or reasonable cause for non-compliance. Practically, this section enforces the accountability of deductors and ensures that the government receives its due taxes promptly.