Complex sentence: As workers cycle in and out of the project, knowledge of the purpose of aspects of the system can be lost, and rather than clean up these pieces, they are worked around, increasing the complexity and mess of the system.
Split into simpler sentences: As workers cycle in and out of the project, knowledge of the purpose of aspects of the system can be lost. Rather than clean up these pieces, subsequent workers work around them, increasing the complexity and mess of the system.