UNCLE,NOW YOU'RE GETTING ANNOYING.
WITHOUT GIVING A SINGLE REASON BEHIND SUCH YOUR OPINIONS,HECK,NOT EVEN TRYING TO FIND ANSWERS ON YOUR OWN (ALL STUFF IS THERE ON THE INTERNET,GO AND FIND IT!) YOU'RE THROWING ALL THESE AT ME ?! 
DO YOU EVEN FIRST KNOW HOW THE KALASHNIKOV WORKS,TO START WITH ?
Anyway,
Because of economy of these eastern european nations (both before and after USSR times).
One of the major industry in all these Warsaw Pact states was export of the defense products.While the USSR was a big player to start with,all these small states were not that defense giants but they DID / DO have formidable small arms industries there,yet them being smaller economies is one of the main reason why their guns are cheaper compared to the original USSR/Russian made ones.
Depends on a lots of factors.
First of all,All USSR era eastern european AKs were/are indeed of good quality because of strong QC regulations set upon them due to the Warsaw Pact,so you can trust these USSR era stuff as of EQUAL (in some cases,like East German MPi-K / MPi-KM and so,even much better than) to the original Soviet/Russian stuff.
Real Thing started when USSR and Warsaw Pact fell like house of cards,and once tighter regulations became non-existent and in consequence of all these inferior quality stuff started being made and sold in the international market at even more cheaper than before just so they can have some bread to eat,and majority of such stuff started coming to the US market where many of these rifles were panned as being of inferior to the russian ones,as Russia,even after breakup of the USSR had quite good QC regulations and so on their small arms plants unlike their former warsaw pact friends.
Then,there is this civilian stuff being sold to the US and other markets where QC regulations were further screwed up like hell,then all NFA regulations set upon import stuff further screwed it all up so now they have to specifically make these stuff as per civilian standards.
Though after some time,their economies became stable again and other issues related to QC regulations were resolved,so now they're back to the original stuff.
Finally,at the very basics they were exact copies of AK-47s/AKMs as i stated in my posts above,so with proper QC Regulations they were/are able to make quite equal,if not better,quality of firearms to the original.Just because they were cheaper doesn't necessarily mean they're inferior,so please get over it!
SERIOUSLY,WHY AREN'T THESE CALLED AK-47 RIFLES ?
Ok,this is the question which could be made as long as you want,but i'll try to keep it as short as i can (because you're fuckin' annoying,Uncle,that's why).
What you call AK-47 and so,is actually a generic term,a common noun generally used to refer all Kalashnikov Derivatives mostly used where one is not sure of actual name of the rifle.
Now,coming to your question,WHY THESE RIFLES HAVE DIFFERENT NAMES ? BECAUSE THESE ARE DIFFERENT RIFLES MADE IN DIFFERENT NATIONS BASED ON SAME DESIGNS I.E. AK-47 AND/OR AKM !
All these designations have their own meanings,mostly initials mean their official designations and end years shows the year when production of all these firearms started.
Then there are language differences,as
AK -
Abtomata
Kalashnikova i.e. Kalashnikov's Automatic Rifle (even then,it's true translation is "Kalashnikov's Submachine Gun" or "Kalashnikov's Automatics",with Automatics term referring to Assault Rifle,Automatic Rifle or even Submachine Gun,though they have a dedicated term PP i.e. Pistolyet-Pulemyot = machine pistol to denote Submachine Guns
) in Russian.Examples here are AK-47,AKM,AK-74 and so
MPi -
Maschine
Pistole i.e. Machine Pistol or Sub-Machine Gun in German (i.e.then East Germany here),examples being MPi-K where K is Kalashnikov,MPi-KM i.e. MaschinePistole Kalashnikov Modernisiert (Modernised i.e. version of AKM)
I really can't write explanations of names of all these different rifles,just google them.
What,seriously,you mean since MARCOS use AK-103 it makes these eastern european AKs inferior in quality ? Then what would you call this different Para guys still using Romanian and East German AKs,nowadays with those saaxy FAB Upgrades and so ?
Coming back to your question,
I really can't answer this,mainly because what was there in MARCOS' requirement to obtain those 103s is completely unknown to me.
And if you're comparing 103s with those USSR era eastern euro AKs then again,this is comparing Pentium 4 to Core i7 as 103 is 21st century derivative of AK-74M (which came out around 1991) in 7.62 x 39mm,a helluwa upgraded variant than these eastern euro guns which are based on warsaw pact era designs i.e. AK-47 and AKM.
If you are really willing to compare 103 with current gen eastern euro AKs then you should look at these ones...
Beryl from Poland
Zastava M21 from Serbia
Rest,if you're comparing USSR era Soviet/Russian AKs with USSR era eastern bloc AKs,then they're quite equal to ORIGINAL ones.
I am not saying there're not bad AKs and so,especially from these nations,but i've shared some reasons why they're equally good or bad and based on those reasons all i want to say is Warsaw Pact era eastern euro AKs for military are as good as original russian ones,then "mileage may vary" based on countless conditions,some of them i've mentioned in my previous posts,some in this post.
Then There're other reasons,too,like using parts not fully compatible with particular rifle,using non compatible ammo/low quality ammo,magazines and so that often results in catastrophe.
^All these things apply to original russian AKs,too.
but what reasons you gave about this posts of yours ? so far,not a single one!
Finally,
Uncle,I think you're just being 'pro-indian army's choice' here.Just because IA is going with AK-103 you're praising it with such a 'BHAKTI' that all other Kalashnikov derivatives are worth dust to you,all kalashnikov derivatives that are not ORIGINAL RUSSIANS are just not worth comparable and so.
Sure it's best choice to go with AK-103 (actually we're going with AK-103M i.e. one shown below) but both your knowledge and thinking is quite limited.
AK-103M
and frankly i don't even care what the fuck you think anymore,yha bas me akela hi kutto ki tarah bhonk raha hu...backstory,reasons etc de raha hu aur tumne ab tak kya samajme aaye aisa reason diya,Unkil ? tumhe toh yeh bhi samaj nahi hain ki in sab ke naam alag alag kyoun hain aur aaye bada AK pe gyaan pel ne....
This will be my last post on this topic.I am simply retreating from here.
