I've bee watching my shares according to the stats page.
I was wondering why my miner keeps switching from block to block?
Sometimes the miner stay's with a block for hours and sometimes it's just minutes even though there are still confirmations left.
Would someone be able to explain?
I was under the understanding the longer you stay the better the payout?

All times are in UTC.
#          Block found at                  Duration   Total shares     Your shares   Your BTC reward Block #   Block value   Validity
21551    2014-01-27 01:17:54    0:56:44    633018888    41600    0.00169053    282635    25.14774250    98 confirmations left
21550    2014-01-27 00:21:10    4:14:43    2821235576    190874    0.00156324    282631    25.02511907    94 confirmations left
21549    2014-01-26 20:06:27    1:19:21    877146598    62015    0.00194748    282605    25.19078729    68 confirmations left
21548    2014-01-26 18:47:06    0:02:01    21876094            1320    0.00146207    282598    25.02195614    61 confirmations left
21547    2014-01-26 18:45:05    4:09:16    2712493846    189101    0.00167564    282597    25.09475048    60 confirmations left
21546    2014-01-26 14:35:49    3:27:45    2220629949    159487    0.00166515    282567    25.04965451    30 confirmations left
21545    2014-01-26 11:08:04    0:40:34    452879502    28531    0.00134326    282539    25.05338644    2 confirmations left
21544    2014-01-26 10:27:30    8:33:05    5735546676    398514    0.00190518    282534    25.00764282    confirmed
21543    2014-01-26 01:54:25    7:49:54    5122146689    364080    0.00176006    282487    25.05767828    confirmed
21542    2014-01-25 18:04:31    2:12:40    1402241422    100815    0.00155369    282429    25.09640344    confirmed
21541    2014-01-25 15:51:51    3:44:41    2363550548    173571    0.00165219    282416    25.10645252    confirmed
21540    2014-01-25 12:07:10    0:54:55    591558361    41783    0.00186171    282388    25.05837209    confirmed

Thanks,