Cheap pens skip, leak, and feel like writing with a stick. This makes writing actually enjoyable.
Why Not Just Buy the Cheap One?
The Kaweco Liliput has a precision German nib with consistent ink flow and actually enjoyable feedback; budget fountain pens have nib alignment issues that cause skipping mid-sentence and feeds that dry out or flood. The brass barrel develops a beautiful patina while cheap plastic yellows and cracks.
The Buy-Once Math
You'll abandon five $8 pens because they write like broken straws, then buy replacement cartridges for $2 each ($50 total frustration). The Liliput costs $30 and writes so well you actually use it daily for a decade. You're not replacing it, and you're saving money on ballpoints you never wanted in the first place.