pecha kucha why estimates make me frown
TRANSCRIPT
WHY ESTIMATES MAKE ME FROWN
ಠ╭╮ಠ
DO
YO
U S
MIL
E W
HE
N Y
OU
ES
TIM
AT
E?
ESTIMATE
GUESS
Empirically derived intelligent
GUESS GUESS
Empirically derived,
consensus based
intelligent
IF ESTIMATES WERE ACCURATE WE WOULD CALL THEM FACTS
EXPERT JUDGEMENT BASED
STATISTICAL ANALYSIS BASED
EXPRESSED AS A “RANGE”
EXPRESSED IN PROBABILITIES OR PERCENTILE CONFIDENCE
Guesses on Known-Knowns and Tolerance for Known-Unknowns
WHAT YOU KNOW YOU KNOW
What you know you don’t know
What you don’t
know, you don’t
know
“I DON’T KNOW”
ESTIMATES PREDISPOSE US TO A SOLUTION
Benefits
Estimates ES
TIM
AT
ES
A
NC
HO
R B
EN
EF
ITS
benefit
time
time to market (?)
ac
tua
l m
ark
et
be
ne
fit
(?)
UNCERTAINTY
Cost to estimate
Time spent to estimate
benefit
time
In order to arrive at any “estimate”
(i) Some TIME is spent AND
(ii) There is a COST to arrive at this estimate
NO SUCH THING AS A FREE LUNCH
estimate
Also, loss of benefit outcomes that
were available ONLY if we had began
work instead.
benefit
estimate
Start “Work”
BAD BUSINESSWhen cost to arrive at
Estimate is greater than the
actual benefit derived from
work, it is just bad business
Projects that get cancelled or
drastically reduced in scope
after months of estimating
effort.
Bre
ak-E
ve
n P
oin
t
SADDLE UP MY UNICORN
benefit
timeestimate
break-even
Start “Work”
Ab
an
do
nm
en
t
I don’t
think a
unicorn
exists
Maybe we
should give
up
ESTIMATES ADD TO ILLUSION OF FEASIBILITY
What? !!,
and have
Nothing to
show
for our
efforts!
We still
have
some
time left,
lets keep
looking
benefit
timeestimate abandon
break-even
Start “Work”
PENALTIES FOR EARLY DELIVERY
Reduced Budget next-cycle
Gold Platting
Pursuit of perfection over good-enough
Peer Pressure: You are making us look bad
Feature Creep - More is better
Benefit from Delivering on
Estimate > Benefit from
Delivering Early
benefit
timeestimate
“expected” or “accepted”
tolerance zone
abandon
break-even
Start “Work”
actual
“best” OR “least-worst” Outcome
PENALTIES FOR LATE DELIVERY
Dependency Domino
Poor quality of product
Poor quality of life of people working on product
“Estimates help build an illusion of
schedule - guile us into passing risk
down the chain until this risk
balloons into an unmanageable
fiasco”
benefit
timeestimate
“expected” or “accepted”
tolerance zone
Time spent to estimate
Cost to estimate
Start “Work”
ANCHORING EFFECT
Awareness of Estimate has
“pinching” effect - Eroding
benefits from outcomes when
work is completed outside of
tolerance zone.
benefit
time
benefit
time
ESTIMATING CONSTRAINTS OUTCOMES WITHIN INVERTED U-SHAPE
THAT’S WHY I FROWN ಠ╭╮ಠ
benefit
time
benefit
time