Frequent causes are writing posture and pressure behaviour: left-handers and writers with an untypical posture angle or high contact pressure often do not get along with Montblanc nibs from OM upwards. Every nib is individually ground and written in, which is why the usual nib width of other manufacturers cannot be directly transferred; in a boutique the after-sales service can re-grind nibs or exchange them. The choice of ink also plays a role, since some inks harmonise poorly with Montblanc's feed system; Montblanc ink in Montblanc pens reduces problems. Generally, manufacturers like Omas with ebonite feeds offer a more saturated ink flow, but they dry out faster and tend more to leak.