Difference between Unreliable and Erratic

UNRELIABLE vs ERRATIC: NOUN

A rock fragment that has been transported by ice to a location other than its place of origin and that may range in size from a pebble to a large boulder.
Anything that has erratic characteristics.
A rock moved from one location to another, usually by a glacier.
One who or that which has wandered; a wanderer.
Specifically In geology, a boulder or block which has been conveyed from its original site, probably by ice, and deposited at a distance; an erratic block. See erratic blocks, under I.
An eccentric person.
One who deviates from common and accepted opinions; one who is eccentric or preserve in his intellectual character.
A rogue.
Any stone or material that has been borne away from its original site by natural agencies; esp., a large block or fragment of rock; a bowlder.

Having no fixed course
Liable to sudden unpredictable change
Likely to perform unpredictably
Having no fixed or regular course; wandering.
Lacking consistency, regularity, or uniformity.
Unsteady, random; prone to unexpected changes; not consistent
The phenomena which relate to transported materials on the earth's surface.
Masses of stone which have been transported from their original resting places by the agency of water, ice, or other causes.
Irregular; changeable.
Deviating from a wise of the common course in opinion or conduct; eccentric; strange; queer.
Deviating from the customary course in conduct or opinion; eccentric.

In zoology, occurring in an unusual location.
Wandering; having no certain course; roving about without a fixed destination.
Deviating from the proper or usual course in opinion or conduct; eccentric.
Moving; not fixed or stationary: applied to the planets as distinguished from the fixed stars.
In medicine, irregular; changeable; moving from point to point, as rheumatic or other pains, or appearing at indeterminate intervals, as some intermittent fevers.
In geology, relating to or explanatory of the condition and distribution of erratics. See II., 2.
Sometimes it would start and sometimes it wouldn't"

Incorrect, Reliable, Inaccurate, Untrusty, Uncertain, Treacherous, Irresponsible, Dangerous, Temperamental, Unsafe, Unsound, Fallible, Erratic, Untrustworthy, Undependable

Volatile, Uneven, Unpredictable, Inconsistent, Changeful, Planetary, Wandering, Quicksilver, Changeable, Fickle, Unsettled, Undependable, Unreliable, Mercurial, Temperamental

Incorrect, Reliable, Inaccurate, Untrusty, Uncertain, Treacherous, Irresponsible, Dangerous, Temperamental, Unsafe, Unsound, Fallible, Erratic, Untrustworthy, Undependable

Volatile, Uneven, Unpredictable, Inconsistent, Changeful, Planetary, Wandering, Quicksilver, Changeable, Fickle, Unsettled, Undependable, Unreliable, Mercurial, Temperamental

They also stated that ALT tests were unreliable.
Rail conditions are poor, limited, and service unreliable.
As a result, waste data is notoriously unreliable.
This just makes you look bitter and unreliable.
Most developing countries have weak and unreliable documents and the poorer people in these countries do not have even those unreliable documents.
Accordingly, because this merger simulation is based upon these unreliable data, the court concludes that the simulation results are likewise unreliable.
An inconsistent or unreliable test produces unreliable results that only inconsistently support the intended inferences of the test.
When faced with expert testimony that contains both reliable and unreliable opinions, district courts often exclude only the unreliable testimony.
It was a case of unreliable statements plus unreliable science.
Unreliable: The Persistent Memory Region has become unreliable.

Welding machines with erratic arcs also waste energy.
Has erratic eating habits, often refusing to eat.
Deviating, erratic, wandering, out of the common way.
That is what causes this erratic, moody behaviour.
By contrast, visceral referral is much more erratic.
Any ideas of why this has erratic function?
MATTHEWS: Well, this all seems pretty erratic, Michael.
Much too often he is erratic and distracted.
Bookchinreflect the characteristic of being uneven and erratic.
Furthermore, their study revealed that waste collection in Gweru is not only erratic but also erratic as waste collectors leave behind some wastes.