MINT6月 2026のための市場シェア分析

In 2025, the temptation to build your own AI agentic system is stronger than ever. With open-source models, APIs, and proof-of-concept demos circulating like wildfire, many marketing leaders ask: “Shouldn’t we just build it ourselves?” But the truth is stark: 75% of in-house AI agent projects will fail—not because teams lack intelligence, but because they underestimate the hidden complexity. From incomplete prototypes to unsustainable maintenance cycles, building a full-fledged agentic media system often ends up draining more time and money than it saves. In this Part I of our 2-part breakdown, we explore four brutal realities of the DIY route—based on real-world pitfalls and expert warnings. If you're a CMO, media director, or data leader contemplating whether to “build vs. buy,” read this first.