In what possible scenario could any beam fleet run out of MSP due to random weapon failures before they have blown your entire fleet into scrap metal?
This is literally a major plot point in my AAR, due to
what turned out to be insufficient maintenance supplies for particle beam-armed ships engaged in sniper duels.It is probably also more common in multi-player-race campaigns, as against NPRs the tactics are usually very simple and players usually outtech NPRs quite badly, but with multiple player races the tactics and tech are much more competitive.
Are some people designing their ships with a higher ratio of engineering spaces to maint storage than I am? Or are others using, say, system defense FACs more often than I do? Or getting into running battles with missile-heavy NPRs that require hours worth of point-defense fire to defeat?
A lot of players, including the Man himself, prefer to put only Engineering Spaces on most ships as these reduce the failure rate and thus MSP consumption rather than just providing more MSPs. Maintenance Bays are really only needed for replenishment ships, or to provide extra MSP to repair weapons. However if you choose to rely on Maint Bays instead of Engineering Spaces this is less of a problem since you have more MSP onboard (but a higher failure rate).
Personally for beam ships I will usually put enough Engineering Spaces to get the maintenance/failure values I want, then add MSPs until I feel like I have enough to keep my weapons operational in a long engagement.
Note that point defense fire does not incur a risk of breakdown, for balance reasons I assume.