Step 1: Understanding the question.
The question focuses on the role of controlling in improving a future process with insights from past experiences.
Step 2: Analyzing the options.
- Controlling: While controlling involves monitoring performance, it doesn’t directly improve future processes.
- Coordinating: Coordination is essential for managing activities but doesn't directly improve future processes based on past performance.
- Communication: Communication is vital but not directly linked to improving future outcomes from past experience.
- Planning: Planning is the function that benefits the most from controlling, as it incorporates past data and information to improve future strategies and actions.
Step 3: Conclusion.
The correct answer is Planning, as controlling provides the necessary feedback to refine future plans.
Final Answer:
\[
\boxed{\text{The correct answer is (4) Planning.}}
\]