Heliogravure How And Why ?

Previous to finding Nethyryk's post of 1979 (Scott #1627)
http://goscf.com/t/5754&whichpage=7#158217 br /
I thought the only stamp produced by Heliogravure of FRANCE
was the 1f50 Exposition Coloniale of 1931.

Now I have found one from Romania (B203 >) 1943

From my cursory Googles, the process seems to be involved,
so why do these countries, move away from the typical engraved Typo or Litho, and employ this method ?

Curious

Rod,héliogravure is called photogravure in English. Masses of stamps are printed by that method.

Oh! that caught me "leg before wicket "
So "Gravure" or "photo" include "rotogravure"

I was expecting a differing process.

2009
This month marks 75 years since the introduction of photogravure print­
ing British stamps, a process still preferred by Royal Mail for definitives.
Photogravure stamp printing was started in Germany in 1914 when F A
Bruckmann produced stamps for Bavaria, which to this day are regarded
as an excellent use of this process.

The Bavarian stamps were clearly an
important development, and it was not long before Mexico (1917), Britain
(the 1918 Waterlow War Tax stamps), Czechoslovakia (1919), Bulgaria and
Wurttemberg (1920) followed Germany's lead. In 1921 Harrison printed 6d
National Savings stamps by photogravure, and started a love affair with a
printing process that would later be so significant to them.

The British stamp in question,

Spanish: huecograbado.
Dutch: rasterdiepdruk (sounds very German).

Another name in German for photogravure is rakeltiefdruck.
That term was noted in the introduction of older Michel catalogues
but then disappeared.

Rakel translates as
wide, thin steel strip, with which excess ink is wiped off the inked printing form during gravure printing

Which in English would be a doctor blade.

Photogravure is one type of Rakeltiefdruck. The EME gravure and electro-gravure processes also are Rakeltiefdruck, but not photogravure.

That might explain why the word is no longer used by Michel.