I'm not a ham but I want to become one later

Any antenna is better than no antenna. Good antennas are both expensive and large, which makes them poorly marketable. A bad antenna can't hurt a receiver, but it can hurt a transmitter. An antenna that doesn't hurt the transmitter isn't necessarily a "Good" antenna either... From the factory, the rubber ducky antenna on radios are optimized for portability and price, not performance. So optimizing one's antenna for the task at hand is the entire hobby for many hams.

But also... Higher frequencies have shorter antennas. A "Good" antenna for 1.8MHz is a much different beast than an equivalent antenna for 1.2GHz; The former requires a large rural property... The latter is only a couple of inches long.

/r/HamRadio Thread