Lessons Learned from Leading a 20‑Person Development Team: Management Mistakes and Reflections

I was an unqualified technical director who, over the past three months, pulled more than 20 members from a 40‑person R&D team (requirements, development, testing) to tackle four legacy projects, working long nights and weekends, only to return with painful lessons.

Project and Team Background

Four projects in three months, no formal project manager, only three intern PMs.

Intern PM experience varied: one had a year on a small continuous project (3 people), another a month on a 4‑person project, and the third half a year on two medium‑size projects (7 people total).

Developers were relatively young; the most experienced had only three years.

The team was split evenly between senior and junior members, with over half having less than a year at the company.

All four projects were built on the same outdated client‑provided framework.

The client’s base framework was over ten years old; the front‑end used a very niche technology with a steep learning curve.

The framework was chaotic, containing nearly 2,000 tables and mixed business code that had to be used.

Development environment setup was difficult; projects ran on Linux and required remote debugging, with long build times (≈10 minutes per compile).

Coordination with many other departments of the large client company consumed more than half of the effort.

Mistake One: Over‑Estimating Team Capability

I assumed I knew my colleagues well, but my understanding was superficial; past stable projects gave me a false sense of confidence.

The team struggled to adapt to the new environment, wasting time in the first two weeks without tangible output.

Examples: a newcomer (A) was placed in a critical role despite poor SQL skills; another experienced member (B) lacked risk awareness, causing repeated delays.

Reflection

Comprehensive assessment and feedback are essential.

Assess people by working closely with them on the same project, observing attitude, efficiency, code quality, coordination, and communication.

Gather multiple perspectives; avoid single‑source judgments.

People evolve; avoid static views and continuously update assessments.

Do not type‑cast individuals based on isolated performance; consider their full history.

Mistake Two: Under‑Estimating Project Difficulty

All four projects (IE‑only) required integration with custom middleware, ActiveX plugins, and various hardware devices—areas we had no prior experience with.

Documentation was missing; we had to reverse‑engineer code and rely on ad‑hoc queries.

The front‑end used a 2006 framework, leading to a steep learning curve and significant delays.

Cross‑department communication was far more difficult than anticipated; we spent hours locating simple hardware specifications.

The client’s framework was far larger than expected (≈2,000 tables, millions of lines of legacy code), making feature discovery arduous.

Reflection

Experience is valuable but can become a liability if it blinds you to missing information.

Proactively seek additional information and verify assumptions.

Identify core project challenges early and use elimination methods to focus on critical components.

Construct a functional relationship diagram (business architecture) for the core elements.

Mistake Three: Tactical Errors – Taking on Too Many Projects Simultaneously

Handling multiple projects with insufficient staff was a strategic mistake, though the decision involved trade‑offs.

Project acceptance should be a careful game theory analysis of feasibility and resource availability.

Reflection

Resource scarcity is inevitable; never assume ideal staffing.

Success often comes from making the best of sub‑optimal resources, akin to winning with a weak hand in a card game.

Mistake Four: Management Is Not Easy

When a project lacked a dedicated lead, I stepped in, which fragmented my ability to coordinate across all projects.

Management demands dedicated effort, especially for communication and coordination in hardware‑intensive projects.

Being immersed in detailed development reduces capacity for oversight.

Delegation is crucial, but regular checks are equally important to ensure deliverables are complete and not re‑work.

Summary of Lessons Learned

Establish a comprehensive assessment and feedback system to truly understand the team.

Do not rely solely on past experience; communication outweighs everything.

Reflect on each tactical mistake to improve precision in future actions.

Assign dedicated managers who stay out of development details to avoid fatal risks.