In school there were 2 obvious different
1ST- switch on the tube starts to very dimly flicker and gradually increase into full brightness over 2/3 secs. On failure, the lamp goes black at one end and just continues to flicker constantly very quickly and dimly (not like s/s flashing).
2ND- switch on the tube glows bright at each end and hums very loudly and lights very quickly. On failure, when it is switched on, the lamp glows at each end, hums very loudly and then cuts out before lighting fully. You cannot get it to ever light fully again.
3RD- some subway fittings we have from 80s. Have a Parmar starterless choke and capacitor in series. When switched on the lamp just lights after a second. No flashing at all.
If anyone can suggest what is what here i'd be much enlightened.