Why fictional FTL drives need consistent limits

How would faster-than-light travel limited to specific locations around a star system affect science-fiction fleet warfare?

Consistent limits can make the setting coherent and explain why fleets cannot simply launch FTL attacks on inhabited planets or appear directly above their objectives.

Faster-than-light travel works as a fictional device when ships using the same principle face consistent limitations. One example combines a compression drive with an instantaneous wormhole drive that cannot be interdicted, giving the two systems different advantages and restrictions. Limiting where a drive can operate also addresses the problem of FTL missiles striking planets or troopships jumping directly onto government buildings. Without some restriction, ordinary fleet combat can become difficult to justify within the story. The criticism of Star Trek and Star Wars concerns changing those rules for a particular scene, including the precision required to emerge from hyperspace beneath a planetary shield.