inefficiency

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The quality, condition, or fact of being inefficient.
• noun An inefficient act, design, or procedure.

from The Century Dictionary.

• noun The condition or quality of being inefficient; lack of efficiency; incompetency; inadequacy.

from the GNU version of the Collaborative International Dictionary of English.

• noun The quality of being inefficient; lack of power or energy sufficient for the desired effect; inefficacy; incapacity.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Lack of efficiency or effectiveness.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun unskillfulness resulting from a lack of efficiency