TLDR: You'll stop yourself from going into "flow state".

The Pomodoro Technique and Coding
The Pomodoro Technique involves breaking work into intervals, traditionally 25 minutes in length, separated by short breaks. However, when it comes to coding, this technique might not always be the best fit.

Coding often requires deep concentration and immersion in the task at hand, a state commonly referred to as 'flow'. This is THE technique/mechanic that will enable you to produce high-quality work and solve complex problems more efficiently 🚀

I can say that, as a junior dev, I tried to force this technique on my work, because it's exactly what I used to do at university. I was simply doing what already worked for me. Here's the issue though, research shows that entering the state of flow will take around 20–50 minutes of working on a given task. The Pomodoro Technique, with its frequent breaks, can disrupt this flow. 

Use this technique to learn how to code, not to actually code at work!