Reality is a messy place.
The Future of Operational Research is Past by Russell Ackoff (paper, 1979).
Managers are not confronted with problems that are independent of each other, but with dynamic situations that consist of complex systems of changing problems that interact with each other. I call such situations messes.
Dilemmas in a General Theory of Planning by Horst W.J. Rittel and Melvin M. Webber (paper, 1973).
The wicked problems paper.
The science of "muddling through" by Charles E. Lindblom (paper, 1959)
The Reflective Practitioner: How Professionals Think In Action by Donald A. Schön (book, 1984)
The Archetypes of Human Work: 1. The Messy Reality by Steven Shorrock (blog post, 2017)
The Messy Details: Insights From the Study of Technical Work in Healthcare by Christopher P. Nemeth, Richard I. Cook and David D. Woods (journal issue, 2004)
The Mathematical Disposition of Structural Engineers by Julie Gainsburg (paper, 2007)
Flexible Sketches and Inflexible Data Bases: Visual Communication, Conscription Devices, and Boundary Objects in Design Engineering by Kathryn Henderson (paper, 1991)
On Line and On Paper: Visual Representations, Visual Culture, and Computer Graphics in Design Engineering by Kathryn Henderson (book, 1999)
Designing Engineers by Louis Bucciarelli (book, 1996)
Engineering and the Mind's Eye by Eugene Ferguson (book, 1992)
The Design of Design: Essays from a Commputer Scientist by Fred Brooks Jr (book, 2010)
Seeing Like a State: How Certain Schemes to Improve the Human Condition Have Failed by James C. Scott (book, 1998)
The Black Swan: The Impact of the Highly Improbable by Nassim Nicholas Taleb (book, 2007)
A City Is Not A Tree by Christopher Alexander (paper, 1965)
The Systems Bible: The Beginner's Guide to Systems Large and Small (originally published as Systemantics) by John Gall (book, 1975)
The Death and Life Of Great American Cities by Jane Jacobs (book, 1961)
Data and Reality: A Timeless Perspective on Perceiving and Managing information in Our Imprecise World by William Kent (book, 1978). Get the second edition if you can find it.
Programming is Forgetting: Toward a New Hacker Ethic by Allison Parrish (talk & essay, 2016)
Everything Is Miscellaneous: The Power of the New Digital Disorder by David Weinberger (book, 2007).
Metacrap: Putting the Torch to Seven Straw-men of the Meta-utopia by Cory Doctorow (online, 2001)
Falsehoods programmers believe about names by Patrick McKenzie (blog post, 2010)
Falsehoods programmers believe about time by Noah Sussman (blog post, ?)
Data file for the Frink programming language is a treasure trove of information on the messiness of units.
The Dappled World: A Study of the Boundaries of Science by Nancy Cartwright (book, 1999)
The Disorder of Things: Metaphysical Foundations of the Disunity of Science by John Dupré (book, 1995)
Messy Chemical Kinds by Joyce C Havstad (paper, 2017)
Can mechanistic explanation be reconciled with free-scale constitution and dynamics? by William Bechtel (paper, 2015)
Categorizing the Mental by Eric Hochstein (paper, 2016)
A Generalized Patchwork Approach to Scientific Concepts by Phillipp Haueis (paper, 2021)
Inventing Temperature: Measurement and Scientific Progress by Hasok Chang (book, 2007)