This is strange. Some delegates don't miss any blocks, others miss many. My delegate  node (bitcoiners) seems to be missing a lot of blocks despite being constantly on.
blockchain_list_delegates 0 10
          ID                     NAME           VOTES FOR       VOTES AGAINST           NET VOTES BLOCKS PRODUCED   BLOCKS MISSED
323                  btsjohn         10474081729                   0      0.1047640741 %              19               0
340               bitcoiners          2816857644              300000     0.02817183174 %               6              12
There seem to be a lot of forks though, maybe this is the reason for missed blocks.
 >>> list_errors
default (unlocked) >>> list_forks
[
  570,
  582,
  618,
  634,
  640,
  691,
  705,
  724,
  777,
  793,
  818,
  829,
  832,
  834,
  880,
  883,
  885,
  939,
  944,
  958,
  993,
  1038,
  1041,
  1043,
  1096,
  1099,
  1102,
  1141,
  1144,
  1178,
  1200,
  1203,
  1219,
  1226,
  1239,
  1255,
  1286,
  1299,
  1318,
  1333,
  1341
]
>>> get_info 
{
  "blockchain_head_block_num": 1354,
  "blockchain_head_block_time": "20140621T162730",
  "blockchain_head_block_time_rel": "59 seconds old",
  "blockchain_confirmation_requirement": 302,
  "blockchain_average_delegate_participation": 63.046192259675408,
  "network_num_connections": 6,