Abstraction is a foundational principle in classical software engineering, enabling modularity, reuse, and scalability. However, quantum programs are governed by fundamentally different semantics, unitarity, entanglement, and measurement collapse, which challenge the safe use of classical abstraction mechanisms. This paper identifies a fundamental conflict in quantum software engineering: abstraction practices that are syntactically valid may violate the physical constraints of quantum computation. We present three classes of failure cases where naïve abstraction breaks quantum semantics and propose a set of design principles for physically sound abstraction mechanisms. We further outline research directions, including quantum-specific type systems, effect annotations, and contract-based module design. Our goal is to initiate a systematic rethinking of abstraction in quantum programming, grounded in quantum semantics and informed by engineering scalability.